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200 Years Ago A Level Biology Biology Divided Into Two Parts Mechanical Engineering

HOSA Chapter 2 – Flashcards 74 terms

Kayden Hussain

74 terms

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HOSA Chapter 2 – Flashcards

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Hospitals

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Vary in size and shape and types of services provided

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General hospitals

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Treat a wide range of conditions and age groups; usually provide diagnostic, medical, surgical, and emergency care

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Specialty hospitals

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Provide care for special conditions or age groups (burn hospitals, cancer hospitals, pediatric hospitals)

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Government hospitals

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Operated by federal, state, and local government agencies located throughout the world that provide care for government service personnel and their dependents

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University of college medical centers

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Provide hospital services along with research and education; can be funded by private and/or governmental sources

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Long-term care facilities

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Mainly provide assistance and care for elderly patients or residents; also care for individual as with disabilities, handicap, chronic, or long-term illness

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Residential care facilities

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(Nursing home) provide basic physical and emotional care to individuals who can no longer care for themselves

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Extended care facilities or skilled care facilities

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Designed to provide skilled nursing care and rehabilitative care to prepare patients a residence for return to home environments or other long-term care facilities

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Independent living and assisted living facilities

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Allow individuals who can care for themselves to rent or purchase an apartment in the facility; a la carte

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Medical offices

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Very from offices that are privately owned by one position too large complex is that operate as corporations and employee many physicians and other healthcare professionals

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What services do medical offices provide?

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Diagnosis, treatment, examination, basic laboratory testing, minor surgery, and other similar care

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Clinics or satellite centers

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Healthcare facilities found in many types of health care; some clinics are composed of a group of medical or dental doctors who share a facility or other personnel

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Surgical clinics

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Perform minor surgical procedures; frequently called one day surgical centers

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Emergency care clinics

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Provide a first aide or emergency care to ill or injured patients

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Rehabilitation clinics

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Offer physical, occupational, speech, and other similar therapies

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Substance abuse clinics

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Provide rehabilitation for drug and alcohol abuse

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Specialty clinics

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Provide care for specific diseases; examples include diabetic clinic's, kidney dialysis centers, and oncology clinics

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Outpatient clinics

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Usually operated by hospitals or large medical groups and provide care for outpatients

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Health department clinics

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Offer clinics for pediatric health, respiratory disease, immunizations, and other special services

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Medical Center clinics

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Usually located in colleges or universities; offer clinics for various health conditions; offer care and treatment and provide learning experiences for medical students

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Emergency care centers

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Provide special care for victims of accidents or sudden illness; these services include ambulance services, rescue squads, helicopter services, and airplane services

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Laboratories

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Are often a part of other facilities but can operate a separate healthcare services; can perform special diagnostic tests such as blood or urine tests

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Home health care

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Provide care in patients home, frequently used by elderly and disabled, provide nursing care, personal care, therapy, and homemaking; offered by health departments, hospitals, private agencies, government agencies, volunteer groups, and nonprofits

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Hospice

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Provide care for terminally ill persons who usually have life expectancy is of six months or less; can be provided in the person's home or in a hospice facility

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Mental health facilities

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Treatment for patients with mental disorders or disease; examples include guidance and counseling centers, psychiatric clinics and hospitals, and chemical abuse treatment centers

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Genetic counseling centers

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Work with couples or individuals who are pregnant or considering a pregnancy; can perform prenatal screening tests, check for genetic abnormalities, and explain the results of the tests

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Rehabilitation facilities

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Provide care to help patients with physical or mental disabilities obtain maximum self-care and function

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Health maintenance organization (HMOs)

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Both healthcare delivery systems and types of health insurance; provide total healthcare services that are primarily directed toward preventative healthcare for fee that is usually fix and prepaid; services include exams, basic medical services, health education, and hospitalization or rehabilitation services

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Industrial healthcare centers

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Found in large companies are industries and provide health care for employees of the industry or business by performing basic exams, teaching accident prevention and safety, and providing emergency care

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School health services

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Provide emergency care for victims of accidents or sudden illness, Promote health education, and maintain a safe and sanitary school environment

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Government agencies

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Health services offered at international, national, state, and local levels; tax supported

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World Health Organization (WHO)

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International agency sponsored by the United Nations; compiles stats and information on disease, publishes health information, and investigates and addresses serious health problems throughout the world

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U.S Department of Health and Human Services (USDHHS)

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National agency that deals with the health problems in the United States

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National Institutes of Health (NIH)

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The division of the USDHHS; involved in research on disease

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Centers for Disease Control and Prevention (CDC)

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Another division of the USDHHS; concerned with the causes, spread, in control of diseases and populations

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Food and Drug Administration (FDA)

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A federal agency responsible for regulating food and drug products sold to the public

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Agency for Healthcare Research and Quality (AHRQ)

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The federal agency established to improve the quality, safety, efficiency, and effectiveness of health care for Americans

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Occupational Safety and Health Administration (OSHA)

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Establishes and enforces standards that protect workers from job-related injuries and illness

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Health departments

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Provide health services as directed by the US Department of Health and Human Services; also provide specific services needed by the state or local community; examples include vaccinations, inspections, healthcare clinics, and prevention

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Voluntary or nonprofit agencies

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Supported by donations, membership fees, fundraisers, and federal or state grants; provide health services at national, state, and local levels; Examples include the American Cancer Society, March of Dimes, American Red Cross

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Health insurance plans

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Insurance plan to help pay for the cost of healthcare

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Premium

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A fee the individual pays for insurance coverage to the insurance company

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Deductibles

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Amounts that must be paid by the patient for medical services before the policy begins to pay

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Co-insurance

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Requires that specific percentages of expenses are shared by the patient and insurance company; For example, in an 80-20% co-insurance, The insurance company pays 80% of it and you pay 20%

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Co-payment

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A specific amount of money a patient pays for a particular service, for example, $10 for each physician visit regardless of the total cost of the visit; Paid at the time of service on top of the deductible; before the bill

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If you meet your premium what happens?

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The insurance company send you checks in the mail; reimbursed

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Employer - sponsored health insurance or group

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Insurance coverage through their places of employment, where the premiums are paid by the employer

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Health maintenance organization (HMOs)

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Type of health service plan that provides a managed-care plan for the delivery of healthcare services; a monthly fee is paid for membership, and the fees stay the same regardless of the amount of healthcare used

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What is one advantage of HMOs?

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They cover routine exams and preventative care

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What is one disadvantage of HMOs?

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People can only visit HMO affiliated health care centers, basically a dictatorship of healthcare

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How can an industry or company provide healthcare at lower rates?

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By using a PPO

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Preferred provider organization (PPO)

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Another insurance plan usually provided by large industries or companies to their employees; forms a contract with certain health care agencies to provide certain types of healthcare at reduced rates, prefers

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What do PPOs usually require?

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A deductible and a co-payment; Is in enrollee uses a nonaffiliated provider, The PPO may require co-payments of 40 to 60%

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Medicare

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Offered for people 65 or older, Who has received Social Security benefits for 2+ years, or has end stage renal disease; elderly

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Medicaid

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Offered for people with low incomes, children without public assistance, and disabled or the blind; financial aid

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Medicare consists of how many types of coverage?

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Three

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Type A coverage?

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Hospital insurance

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Type B coverage?

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Medical insurance

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Type D coverage?

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Pharmaceutical/drug expenses

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How much does Medicare actually pay for?

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Only 80% of the services

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Medigap

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Health insurance plans that help pay expenses not covered by Medicare; offered by private insurance companies require the payment of a premium by the enrollee; must meet specific federal guidelines

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Children's Health Insurance Program (CHIP)

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For uninsured children of working families who don't have enough money for Medicaid

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Worker's Compensation

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Health insurance plan providing treatment for workers injured on the job; administered by the state, and payments are made by the employers in the state

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TRICARE

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US government health insurance plan for all military personnel, active-duty members and their families, survivors of military personnel, and retired members of the Armed Forces

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Managed care

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Developed in response to rising healthcare costs; employers, as well as insurance companies who pay large bills, want to ensure that such money is spent efficiently rather than wastefully; basically that all health care provided to the patient must have a purpose

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If you have a pre-existing medical condition and you lose your job, what act protects your excess ability to health insurance coverage?

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HIPAA

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Health Insurance Potability and Accountability Act (HIPAA)

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Establishes guidelines for insurance companies to deny or except people for insurance based on five main components

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How many main components are there in HIPAA?

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Five

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Health care access, portability, and renewability

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Limits it's exclusions on pre-existing conditions to allow for the continuance of insurance even with job changes, prohibits discrimination against and enrollee or beneficiary based on health status, guarantees renewability in multiemployer plans, and provide special enrollment rights for individuals who lose insurance coverage in certain in situations such as divorce or termination of employment

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Preventing healthcare fraud and abuse; administrative simplification, and medical liability reform

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Establishes message for preventing fraud and abuse and imposes sanctions or penalties if fraud or abuse does occur

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Tax related health provisions

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Promote the use of medical saving accounts by allowing tax deductions for monies placed in the accounts, establishes standards for long-term care insurance

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Application and enforcement of group health plan requirements

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Establishes standards that require group health care plans to offer portability, access, and renewability to all members of the group

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Revenue offsets

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Provides changes to the International Revenue Code for HIPAA expenses

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Organizational structure

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The line of authority or chain of command at a hospital that indicates areas of responsibility; essential for the most efficient hospitals

STUDY

A Level Biology AP Biology Biology Compound Light Microscope

Biology: Cell Structure & Function Review Study Guide/ Key Concept – Flashcards 32 terms

Alicia Bennett

32 terms

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Biology: Cell Structure & Function Review Study Guide/ Key Concept – Flashcards

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State the 3 key points of the Cell Theory.

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- All living things are composed of one or more cells. - The cell is the smallest unit having the properties of life. - The continuity of life arises directly from the growth and reproduction of single cells.

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Name the 3 features that all cells have in common.

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1. Plasma Membrane 2. Cytoplasm 3. Nucleiod Region or Nucleus

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Describe the Plasma Membrane feature that all cells have in common.

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- Is the outermost membrane of the cell. - It maintains the cell as a distinct entity/ unit of life.

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Describe the Cytoplasm feature that all cells have in common.

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- The semi-fluid matrix of a cell. - Is found between the Plasma Membrane and Nucleiod Region or Nucleus.

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Describe the Nucleiod Region or Nucleus feature that all cells have in common.

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Depending of the species... Nucleiod Region - The DNA occupies the region of the Cytoplasm. Nucleus - Is surrounded by a membrane.

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Do chromosomes always have the same appearance during a cell's life?

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No, their appearance remain changing during a cell's life.

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Cell Walls are typical of the cells of which organism?

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- All plants, fungi, bacteria and many protistans

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What are the key differences between Prokaryotic Cells and Eukaryotic Cells?

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- Prokaryotic Cells DO NOT have a Nucleus - Eukaryotic Cells DO have a Nucleus

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What is a Cell?

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- Smallest unit of life - Prokaryotic/ Eukaryotic Cell

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What do cells look like?

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- Comes in all shape, sizes and color. - Depends on what organism it is.

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What is a Prokaryotic Cell?

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- Do NOT have a nucleus, nor do they contain any other membrane-bound Organelle. - Simplest cell (Smallest cell). - DNA is not enclosed in a Nucleus. - Have a Plasma Membrane and Cytoplasm.

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What organisms are Prokaryotic Cells?

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- ALL bacteria cells are Prokaryotic. Two kingdoms of Prokaryotic Celled organism - Archeabacteria - Eubacteria

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What are the functions of the Central Vacuole?

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- May take up as much as 50 - 90% of the cell interior. - It allows the cell to maintain its turgidity and stiffness.

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What is a Eukaryotic Cell?

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- Cells that have a membrane-bound Nucleus and other membrane-bound organelles in the Cytoplasm. - Specialized structures that make up the cell and preform functions essential for survival. - ALL Eukaryotic Cells contain organelle.

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What organism have Eukaryotic Cells?

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- You either have a Nucleus or once had a Nucleus.

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What do cells have in common?

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- Plasma Membrane - Cytoplasm - Nucleiod Region or Nucleus

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What is the biological significance of Organelles?

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- Organelles amount to a degree of compartmentalization and therefore a type of specialization. - The compartmentalization allows a large number of activities to occur simultaneously in a very limited space. - Physically separate chemical reactions, many of which are incompatible with each other.

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What are the basic tenets of the "Cell Theory"?

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Who developed the "Cell Theory"?

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- Robert Hooke - Antony Van Leeuwenhoek - Robert Brown * - Matthias Schliedeh * - Theodor Schwann * - Rudolf Virchow

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What is the difference between Chromatin and Chromosomes?

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- Chromatin - Thin and threadlike, has a diffuse granny appearance (not dividing). - Chromosomes - Condenses and shortens into identifiable rod-shaped structure (undergo dividing).

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What is a Plasma Membrane?

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- Is the outermost membrane of the cell.

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What is Cytoplasm?

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- The semi-fluid matrix of the cell.

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Describe the structure and functions of the following Eukaryotic Organelles... Nucelus.

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- Generally the largest and most conspicuous structural area within the cell. FUNCTIONS TO: - Plays a central role in Cellular Respiration. - Plays a key role on determining what the cell wall becomes and what form it will have at maturity. - Directs the metabolic activities of the cell. - In summary - It basically controls the life process of the cell.

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Describe the stucture and functions of the following Eukaryotic Organelles... Rough Enodoplasmic Reticulum.

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- Exists as flattened , fluid-filled, membrane-enclosed sacs. - The rough appearance is due to many ribosomes being embedded in the membranes.

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Describe the structure and functions of the following Eukaryotic Organelles... Smooth Endoplasmic Reticulum.

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- Does not have Ribosomes embedded in it. - Has much more or a tubular appearance. FUNCTIONS TO: - Synthesize membrane phospholipids. - To package proteins in vessels for transport. - As sites for chemical reactions.

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Describe the structure and functions of the following Eukaryotic Organelles... Golgi Bodies.

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- They appear like a stack or plates or pancakes. FUNCTION TO: - Modify lipids and proteins - Sort, packages, and ships to specific locations of the cell or out of the cell.

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Describe the structure and functions of the following Eukaryotic Organelles... Mitochondria.

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- Peanut of globular shaped. - Referred to as the "Powerhouse" of the cell.

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Describe the structure and functions of the following Eukaryotic Organelles... Chloroplasts.

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- Oval or disk-shaped. - Sac-like organelle used for storage

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Describe the structure and functions of the following Eukaryotic Organelles... Lysosome.

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- Digest cellular debris, parts of cells or whole cells.

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Describe the structure and functions of the following Eukaryotic Organelles... Chromoplast.

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- Red to yellow pigments - Store photosynthesis pigments, other than Chlorophylls. - Store Carotenoids

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Describe the structure and functions of the following Eukaryotic Organelles... Amyloplasts.

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- Are not colored - They store starch grains

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Describe the structure and functions of the following Eukaryotic Organelles... Peroxisome.

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- They multiply in a cell via fission

STUDY

A Level Biology Ecology Environmental Science Genetic Engineering

Ecology Unit Test Study Guide – Flashcards 26 terms

Sara Graham

26 terms

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Ecology Unit Test Study Guide – Flashcards

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Ecosystem

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A biological community of interacting organisms and their physical environment.

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Population

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A group of individuals that belong to the same species and live in the same area

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Community

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A group of interdependent organisms inhabiting the same region and interacting with each other

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Organism

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An individual living thing

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Symbiosis

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A close relationship between two species that benefits at least one of the species.

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Mutualism

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A relationship between two species in which both species benefit

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Commensalism

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A relationship between two organisms in which one organism benefits and the other is unaffected

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Parasitism

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A relationship between two species in which one species, the parasite, benefits from the other species, the host, which is harmed

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Predator

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An animal that naturally preys on others

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Prey

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An organism that is killed and eaten by another organism

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Biome

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A group of ecosystems that share similar climates and typical organisms

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Producer

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An organism that can make its own food.

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Decomposer

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An organism that breaks down wastes and dead organisms

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Consumer

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An organism that obtains energy by feeding on other organisms

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Omnivore

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An animal that eats both plants and animals

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Carnivore

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Organism that obtains energy by eating animals

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Herbivore

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A consumer that eats only plants.

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Nutrient Cycle

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The movement of materials (nutrients) in a local ecosystem

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Carbon

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a colorless, odorless gas produced by burning carbon and organic compounds and by respiration. It is naturally present in air (about 0.03 percent) and is absorbed by plants in photosynthesis.

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Water

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H2O

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Nitrogen

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The most abundant gas in the atmosphere

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Carrying Capacity

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Largest number of individuals of a population that a environment can support

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Limiting Factor

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Any biotic or abiotic factor that restricts the existence, numbers, reproduction, or distribution of organisms.

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Biotic

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Living parts of an ecosystem

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Abiotic

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A term that describes a nonliving factor in an ecosystem.

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Trophic Levels

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levels of nourishment in a food chain

STUDY

A Level Biology Biology Genetics

Biology Chapter 12 Test – Flashcards 31 terms

Ethan Carter

31 terms

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Biology Chapter 12 Test – Flashcards

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DNA replication results in two DNA molecules:

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Each with one new strand and one original strand.

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Why did Hershey and Chase label the viral DNA with radioactive phosphorus and not radioactive sulfur?

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DNA contains phosphorus and no sulfur

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which of the following is a nucleotide found in DNA?

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deoxyribose and phosphate group and cytosine

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During DNA replication, a DNA strand that has the bases CTAGGT produces a strand with the bases:

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GATCCA

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which part of the bacteriophages in figure 12-1 contains genetic material?

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DNA makes a good molecule for storing information because:

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Its bases can be joined together in any order, like the letters of the alphabet can be strung to form different words.

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which bacteria killed the mice in Griffiths transformation experiment?

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live harmless bacteria and heat killed harmful bacteria

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what stores information in a Cell?

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DNA

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what did rosalind franklin contribute to the effort to identify the structure of DNA?

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X-ray diffraction photos of the DNA molecule

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In both eukaryotes and prokaryotes, how many copies of the chromosomes are left after replication?

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Which of the following include all the others?

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Chromosomes

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What did avery conclude caused transformation?

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DNA was the transforming factor

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In both prokaryotes and eukaryotes, DNA replication happens:

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Before cell division

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What binds to the prokaryotic chromosome to start DNA replication?

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Regulatory proteins

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Which scientist made x-ray diffraction photos of DNA?

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Rosalind Franklin

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Because of base-pairing in DNA, the percent of:

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Thymine molecules in DNA is about equal to the percent of adenine molecules

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Which forms a base pair with thymine?

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Adenine

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In eukaryotes, DNA:

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Is located in the nucleus

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Griffith called the process he observed transformation because:

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Harmless bacteria had been transformed

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Which scientist figured out that the shape of a DNA molecule is a double helix?

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Watson and Crick

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Which o the following statements correctly describes Chargaff's contribution to the study of DNA?

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Chargaff showed that adenine + thymine were found in equal percentages in DNA, but he did not know it was because of base pairing

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What do bacteriophages infect?

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Bacteria

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In what way is DNA like a book?

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DNA has stored info, that can be copied and passed from one organism to the other

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Griffith's experiments advanced the study of genetics by proving that:

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There is a chemical that contains genetic information that can be passed from one organism to the other

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If adenine has 30%, guanine will have ___%.

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A prokaryotic cell replicates its ________ before it splits to form new cells, so that each new cell can have genetic material.

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Dna (or chromosomes)

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Explain how bacteria in Griffith's experiment were transformed.

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The harmless bacteria took in dna from the heat killed bacteria.

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When is DNAs role in transmitting info most important and why?

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When the reproductive cells lose information, it means that the offspring will have a loss of information too

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What is bacteriophage?

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A virus that infects and kills bacteria

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Identify 3 main components on the nucleotides. With a, and t

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Adenine, thymine, and phosphate

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What do a, c, t, and g stand for?

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Adenine, cytosine, thymine and guanine

STUDY

A Level Biology Anatomy Biology IB Biology Immunology

Unit 12 Quiz – Flashcards 55 terms

Henry Smith

55 terms

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Unit 12 Quiz – Flashcards

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Which of the following is NOT among the common cell types that make up the immune system? A) P-cells B) B-cells C) T-cells D) Phagocytes

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Which of the following describes a known association with coronary heart disease (CHD)? A) In men, CHD begins 10-15 years earlier than in women B) Women who take estrogen to reduce the risk for osteoporosis are at significantly higher risk for CHD C) Men with blood cholesterol levels in the borderline-high range account for up to 10% of all deaths from CHD D) Women younger than 45 years of age tend to have higher LDL cholesterol than do men of that age, but this difference disappears after menopause

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Since 1960, how have blood cholesterol levels and deaths from CVD among U.S. adults changed over time? A) A continuous upward trend for both B) A continuous downward trend for both C) A fall in cholesterol but a rise in CVD deaths D) An upward trend for cholesterol but a reduction in CVD deaths

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What type of substance is resveratrol? A) Lipoprotein B) Antioxidant C) Soluble fiber D) Atherogenic promoter

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Which of the following is a characteristic of factors associated with hypertension? A) Most people with hypertension have BMIs <25 B) Most people with hypertension are extremely salt sensitive C) Three to 4 alcohol drinks per day lowers risk for hypertension D) African Americans develop high blood pressure earlier in life and their average blood pressure is higher than others

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In the measurement of blood pressure, the units are expressed as A) cm of silver. B) cm of depth. C) mm of plaque. D) mm of mercury.

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The percent risk of developing hypertension later in life when the blood pressure is normal at age 55 is A) 0. B) 10. C) 50. D) 90.

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Which of the following statements describes a risk factor for high blood pressure? A) Three alcohol drinks per day increases the risk for developing high blood pressure B) Most people are genetically sensitive to sodium and will develop high blood pressure from excess salt intake C) Ninety-five percent of people under 50 years of age with high blood pressure respond favorably to low salt intake D) Ninety-five percent of people with high blood pressure who restrict salt intake show a significant decrease in blood pressure

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What percentage of people with diabetes have type 1? A) 5-10 B) 10-20 C) 20-35 D) 45-55

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Insulin resistance is defined as A) reduced sensitivity of cells to blood insulin. B) impaired secretion of insulin by the pancreas. C) increased destruction of insulin-producing cells. D) refusal of people with type 1 diabetes to self-inject insulin.

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Among the following ethnic groups, which has the lowest risk for type 2 diabetes? A) American whites B) Asian Americans C) African Americans D) Native Americans

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What is the primary reason for increased urine output in uncontrolled diabetes? A) Insufficient levels of circulating insulin permit the kidneys to lose excess water B) High levels of blood glucose spill into the urine, drawing water with it by osmosis C) Excess circulating insulin affects the output of antidiuretic hormone, which allows greater losses of water D) Large amounts of body fat and glycogen are broken down, resulting in increased release of cellular water

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In the otherwise stable person with type 1 diabetes, a potential problem associated with physical activity is A) hypoglycemia. B) hyperglycemia. C) nausea and vomiting. D) temporary kidney shutdown.

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What term describes factors that enhance the development of cancer after it has been initiated? A) Promoters B) Post-initiators C) Tumor formatives D) Tumor directives

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What term describes an abnormal cell mass that is not cancer? A) Benign tumor B) Promoting tumor C) Malignant tumor D) Premalignant tumor

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A substance that causes cancer is termed a(n) A) carcinogen. B) antipromoter. C) DNA-modifier. D) RNA-modifier.

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Which of the following cooking techniques for meats results in the least formation of carcinogens? A) Frying B) Grilling C) Broiling D) Marinating before cooking

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Which of the following is known to speed up the passage of substances through the large intestine, thereby decreasing exposure time to carcinogens? A) Milk B) Fiber C) Omega-3 fats D) Refined starches

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Conventional medicine and alternative medical therapies are commonly linked together into a practice called A) interactive therapy. B) yin and yang medicine. C) herbal-assisted healing. D) complementary medicine.

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What treatment is effective against lead poisoning and is also considered an alternative therapy for cardiovascular disease? A) Ozone injections B) Chelation therapy C) Biofield therapeutics D) Hydroexpulsion therapeutics

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What are cytokines? A) Scavengers of the immune system B) Specialized antibodies that retain B-cell memory C) Specialized proteins that activate responses to infection D) Highly specific cells that attack only one type of antigen

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Kimmy is a curious 4-month-old baby who is just learning how to crawl. On Monday she came across some large dust particles underneath the couch, which caused her to sneeze and develop a runny nose and a cough. Two weeks later she came across more dust from the same place. Which of the following aspects of immunity allows Kimmy's body to remember how to respond to this dust again? A) T cells B) B cells C) Beta cells D) Spleen cells

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Which of the following is a feature of AIDS? A) It has no cure B) Its prevention depends on good nutrition C) It cannot pass from mother to infant during breastfeeding D) It is among the 10 leading causes of death in the United States

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Approximately how many people in North America have HIV or AIDS? A) 100,000 B) 550,000 C) 1.5 million D) 3.3 million

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Which of the following leading causes of death in the United States does NOT bear a relationship to diet? A) Cancer B) Heart disease C) Diabetes mellitus D) Pneumonia and influenza

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By what age do most people first have well-developed arterial plaque? A) 30 B) 40 C) 50 D) 60

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The obstruction of a blood vessel by a clot that broke away from arterial plaque is termed A) an anginism. B) an embolism. C) circulatory hypoxia. D) a de-plaquing event.

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What is prehypertension? A) A predictor of stroke risk B) Slightly high blood pressure C) A precursor for Syndrome X D) A component of the metabolic syndrome

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What blood cholesterol carrier is of greatest concern in atherosclerosis? A) HDL B) LDL C) HDK D) VLDK

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Stefan was recently diagnosed with metabolic syndrome. He is very scared about this new diagnosis because no one in his family has ever had it and he hasn't ever heard of it. His primary care physician refers him to your office for some counseling on his modifiable risk factors. Which of the following topics will you most likely discuss with Stefan? A) What medications to take B) How to improve his atherogenic diet C) How to slow down his aging process D) How to map out his family tree, identifying all relatives with heart disease

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Diuretics act to lower blood pressure by A) increasing fluid loss. B) decreasing potassium loss. C) reducing arterial plaque formation. D) increasing retention of calcium and potassium.

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Which of the following is a characteristic of type 1 diabetes? A) It is an autoimmune disorder B) It occurs exclusively in people under 40 years of age C) It must be treated by daily oral intake of insulin pills D) It accounts for approximately 50% of all cases of diabetes

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question

Gangrene is a common complication primarily in people with A) cancer. B) diabetes. C) pancreatitis. D) HIV infection.

answer

question

Which of the following is NOT among factors known to correlate strongly with risk for cancer of the head and neck? A) Tobacco use B) Alcohol intake C) Food additives and pesticides D) Low intake of vegetables and fruits

answer

question

Which of the following foods is known to contain abundant amounts of phytonutrients that protect against cancers of the esophagus and endometrium? A) Fermented dairy foods B) Cruciferous vegetables C) Allium-rich vegetables D) Lycopene-rich vegetables

answer

question

Potatoes that are fried or baked at high temperatures are a source of the carcinogen A) glioma. B) creatine. C) acrylamide. D) benzo(a)pyrene.

answer

question

Why is complementary and alternative medicine considered to be unconventional medicine? A) It is not taught in medical schools B) Insurance companies refuse to cover it C) Safety and effectiveness are not well established D) It is used primarily by chiropractors and herbalists

answer

question

What is the name of the cancer-treatment substance first extracted from the bark of old Pacific yew trees (and now synthesized in the laboratory)? A) Ephedra B) Paclitaxel C) Kombucha D) Germanium

answer

question

Which of the following is a characteristic of HIV or AIDS? A) HIV but not AIDS is curable B) AIDS develops from HIV infection C) Optimal nutrition can prevent but not cure HIV D) Since the 1990s, the death rate from HIV and AIDS has increased markedly

answer

question

The ballooning out of an artery wall at a point where it has been weakened by deterioration is called a(an) A) aorta. B) plaque. C) aneurysm. D) diverticula.

answer

question

Which of the following may be classified as a risk factor for coronary heart disease? A) BMI of 26 B) Low LDL-cholesterol levels C) High HDL-cholesterol levels D) High C-reactive protein levels

answer

question

Which of the following is a characteristic of gender and coronary heart disease? A) There are fewer deaths from CHD in women than in men B) At every age, men have a higher risk for CHD C) The rate of CHD suddenly accelerates after menopause D) After age 55, aging becomes a risk factor for CHD in men but not women

answer

question

Which of the following is a feature of blood triglycerides and risk for coronary heart disease? A) High triglyceride levels are now designated as a major risk factor B) Elevated triglycerides are not an independent risk factor C) High triglyceride levels correlate strongly with high HDL levels, which is a predictor for low risk D) Triglyceride concentrations are low in very-low-density lipoproteins, which correlate with risk for metabolic syndrome

answer

question

Which of the following is NOT among the associations between smoking and coronary heart disease? A) Smoking damages platelets B) Smoking increases blood pressure C) Smoking as a risk factor for CHD is the same for women and men D) Cessation of smoking begins to lower the risk of CHD after 36 months

answer

question

A person who produces a normal amount of insulin but whose cells show suboptimal response is said to be A) polydipsic. B) insulin resistant. C) hyperglucagonemic. D) pancreatic beta-cell deficient.

answer

question

Which of the following is the most likely reason that a blood pressure reading should be repeated before confirming a diagnosis of hypertension? A) The person reacted emotionally to the procedure B) Blood pressure measuring devices often give inaccurate readings C) The cuff of the blood pressure measuring device was wrapped too tightly on the arm D) The cuff of the blood pressure measuring device was wrapped too loosely on the arm

answer

question

What happens to the risk for CVD for a person with a blood pressure of 120/90? A) It is halved B) It is doubled C) It is unchanged D) It is reduced by 25%

answer

question

Peripheral resistance of blood flow is calculated as A) heart rate divided by pulse rate. B) cardiac output times blood pressure. C) ejection volume times stroke volume. D) blood pressure divided by cardiac output.

answer

question

Which of the following is a characteristic of drug therapy for hypertension? A) Antihypertensive drugs work by lowering blood volume B) The most frequently prescribed drug therapies are DASH inhibitors C) Most people with hypertension need only one medicine to reduce blood pressure D) Major side effects of antihypertensive drugs are depletion of body sodium and phosphorus

answer

question

Calcium-channel blockers are drugs chiefly for the treatment of A) atherosclerosis. B) prostate cancer. C) type 2 diabetes. D) high blood pressure.

answer

question

Among the leading causes of death in the United States diabetes ranks number A) 1. B) 3. C) 7. D) 10.

answer

question

In which of the following conditions would the pancreas be unable to synthesize insulin? A) Hyperglycemia B) Type 1 diabetes mellitus C) Type 2 diabetes mellitus D) Adult-onset diabetes mellitus

answer

question

A person with diabetes is most likely to develop A) AIDS. B) cancer. C) heart attacks. D) diverticulosis.

answer

question

What happens after absorption of carcinogens that are produced on meats from grilling over a direct flame? A) They are detoxified by the liver B) They act as initiators for breast cancer C) They act as promoters for prostate cancer D) They are subjected to enterohepatic circulation

answer

question

What is ayurveda? A) A system that combines biofeedback with hypnosis B) An oriental plant that suppresses colon and breast tumor growth C) A Hindu system for enhancing the body's ability to prevent illness and to heal itself D) A variation of standard acupuncture technique that applies electromagnetic impulses to the needles

answer

STUDY

A Level Biology Biology Scientific Method The Environment

Biology A Final Exam – Flashcards 42 terms

Charlotte Small

42 terms

Preview

Biology A Final Exam – Flashcards

question

When conducting a biology investigation, why is it important to note the safety rules and symbols?

answer

to avoid accidents

question

Which is not a product of photosynthesis?

answer

nitrogen

question

A molecule that contains only carbon and hydrogen is called a _____.

answer

hyrdocarbon

question

A cancer treatment that kills unwanted cells with drugs is called _____.

answer

chemotherapy

question

How does water form during cellular respiration?

answer

Oxygen is reduced, gaining electrons and hydrogen ions.

question

CAM plants close their _____ during the day and open them at night.

answer

stomata

question

Actin makes up cytoskeleton fibers called _____.

answer

microfilaments

question

Which kind of molecule does transcription produce?

answer

RNA

question

A pH of _____ is considered neutral.

answer

question

Which scientific skill involves sharing what you have learned with others?

answer

communicating

question

T is a trait for tallness in pea plants. The trait for shortness is t. In a case of simple dominance, what is the height of a plant with the genotype Tt?

answer

tall

question

What do biotechnologists use to cut DNA molecules at specific sequences?

answer

restriction endonuclease

question

Why is it important that a protein keeps its shape?

answer

The shape of a protein allows it to perform its particular job.

question

Energy is captured for photosynthesis by _____ molecules.

answer

chlorophyll

question

The first generation of offspring from the cross of two parents is called the _____.

answer

F1 generation

question

In humans, which sex chromosome determines if an offspring is a male or female?

answer

question

Enzymes are _____.

answer

proteins

question

During which process are food molecules broken down to produce chemical potential energy in the form of ATP?

answer

cellular respiration

question

Which are examples of steroids?

answer

cholesterol and vitamin D

question

During replication, DNA _____.

answer

is copied

question

_____ is a type of cell division that produces gametes.

answer

meiosis

question

Which discovery did not contribute to cell theory?

answer

all cells require ATP for energy

question

What sequence of DNA bases bonds with the DNA base sequence ATGT?

answer

TACA

question

When a substance changes into a different substance, a _____ change has occurred.

answer

chemical

question

In mitosis, chromatids line up in the middle of the cell during _____.

answer

metaphase

question

Which takes place inside the chloroplast?

answer

light and dark reactions

question

Why do athletes often eat lots of carbohydrates the day before a competition?

answer

Carbohydrates give living things energy.

question

An atom of nitrogen has seven protons in its nucleus. How many electrons does it have?

answer

question

The study of living things and their environment is called _____.

answer

ecology

question

Which statement is true?

answer

viruses are not living

question

Organisms use _____ to do work, grow, and change.

answer

energy

question

What factor is a characteristic of passive transport?

answer

it occurs without energy input

question

What is an ion?

answer

an atom or particle with a positive or negative charge

question

What makes up the backbone of a DNA molecule?

answer

sugars and phosphates

question

What do cellular respiration and fermentation have in common?

answer

they both harvest energy from sugars

question

Which term describes a group of cells that are similar and work together?

answer

tissue

question

Which molecules are often embedded within the lipid bilayer to help substances move through the membrane?

answer

proteins

question

What kind of bond is created by the attraction between atomic particles of opposite charge?

answer

ionic bond

question

What feature makes water a polar molecule?

answer

The ends of the water molecule have opposite electrical charges.

question

What is cyclic about the reactions that make up the Krebs cycle?

answer

The first reactant and last product are the same.

question

Which process describes the movement of molecules from areas of high concentration to areas of low concentration?

answer

diffusion

question

Ribosomes are made up of _____.

answer

RNA and protiens

STUDY

A Level Biology AP Biology Biology Cell Biology Identify The Key

bio exam II – Flashcards 31 terms

James Storer

31 terms

Preview

bio exam II – Flashcards

question

A malfunction in the G1 phase of the cell cycle might lead to

answer

a failure of the cell to grow properly in preparation for division

question

What is the fate of sister chromatids during mitosis

answer

They separate in anaphase and become chromosomes in new daughter cells

question

When and why does the nuclear envelope break down during cell replication

answer

during prophase, in order to allow microtubules to attach to the duplicated chromosomes

question

Which of the following factors stimulates a normal cell to divide

answer

growth factors

question

In the absence of growth factors, a normal dividing cell would

answer

stop at the g1 checkpoint

question

True or false: Only individuals with cancer have proto-oncogenes

answer

false

question

Nucleoli are present during _____.

answer

interphase

question

Cytokinesis often, but not always, accompanies _____.

answer

telophase

question

Chromosomes become visible during _____.

answer

prophase

question

Centromeres divide and sister chromosomes become full-fledged chromosomes during _____.

answer

anaphase

question

Spindle fibers attach to kinetochores during _____.

answer

prometaphase

question

During prophase a homologous pair of chromosomes consists of _____.

answer

two chromosomes and four chromatids

question

True or false. Mitosis takes place during M phase of the cell cycle, which is longer than interphase.

answer

false

question

A certain species of animal has six pairs of chromosomes. How many DNA molecules are present in the nuclei of these animals during G2 phase?

answer

question

Which of the following checkpoints does not occur late in G1

answer

A check that chromosome replication has been successfully completed

question

which phase of the cell cycle is linked to DNA repilcation

answer

S-phase of interface

question

Sally is looking at a dividing cell under the microscope. She examines the cell and sees that the nucleus is not present and that the chromosomes are condensed and lined up in the center of the cell. She knows that this cell is in

answer

metaphase

question

Which of the following structures permit(s) communication between eukaryotic cells?

answer

Gap junctions in animal cells and plasmodesmata in plant cells

question

Where does the metabolism of a neuron take place?

answer

cell body

question

What do gap junctions and plasmodesmata have in common?

answer

They both allow material to move from one cell to another.

question

Where are photoreceptor cells found in the eye?

answer

In the retina

question

Why is negative feedback found more often than positive feedback in animal psychology?

answer

Negative feedback changes the direction of a process; positive feedback maintains it.

question

Which of the following is the best example of negative feedback?

answer

Once a thermostat is set for a certain temperature, the furnace will shut off when it reaches that temperature.

question

Where are the principal sensory receptors found in the body that monitor temperature, pain, pressure, and touch?

answer

the skin

question

Your hands are feeling cold. What portion of a neuron has detected this and transmitted the impulse to the nervous system?

answer

the dendrite

question

Bathing, basking, hibernating, and migrating are examples of which type of thermoregulation adaptation?

answer

Behavioral adaptation

question

Fur, fat, and feathers are examples of which type of thermoregulation adaptation?

answer

Anatomical adaptation

question

Where is the organ of Corti found in the ear?

answer

In the cochlea

question

Panting, shivering, and sweating are examples of which type of thermoregulation adaptation?

answer

Physiological adaptation

question

What is the correct sequence of structures that sound waves pass through to be sent on to the brain?

answer

Pinna - auditory canal - eardrum - hammer - anvil - stirrup - cochlea

question

What are olfactory organs?

answer

Olfactory organs contain specialized receptors to detect odors.

STUDY

A Level Biology Biology Cell Biology

Chapter 9: Cell Division and Mitosis – Questions – Flashcards 21 terms

Kevin Stewart

21 terms

Preview

Chapter 9: Cell Division and Mitosis – Questions – Flashcards

question

Following mitosis and cytokinesis, daughter cells are

answer

genetically identical to each other and the parent cell.

question

In the cell cycle, DNA is replicated during

answer

question

What process is critical for embryonic development, wound healing, and replacement of blood cells?

answer

cell division (mitosis and cytokinesis)

question

During which stage of the cell cycle do sister chromatids separate from each other?

answer

anaphase of mitosis

question

During which stage of the cell cycle are sister chromatids initially produced?

answer

S Phase

question

If a cell fails to replicate its DNA completely, what will happen?

answer

It will pause to allow DNA replication to complete.

question

Many drugs interfere with cell division. Why shouldn't pregnant women take these drugs?

answer

The embryo (and later fetus) is growing through the process of mitotic cell division. If the mother took a drug that interfered with cell division, that drug could interfere with normal development of the embryo and fetus, causing birth defects and possibly death of the developing baby.

question

What would be the result if a cell completed interphase and mitosis but failed to complete cytokinesis?How many cells would there be at that point, and how many chromosomes relative to the parent cell would those cells have?

answer

If a cell completed interphase and mitosis but then did not complete cytokinesis, the result would be a single cell with two nuclei. Each nucleus would have the same number of chromosomes as the parent cell. This means that the single binucleate cell would have twice the number of chromosomes as the parent cell.

question

A normal cell that sustains irreparable DNA damage will most likely

answer

die by apoptosis.

question

Which checkpoint prevents a normal cell from completing its cell cycle if it has not accurately replicated its DNA?

answer

interphase (G2-M)

question

After a bad sunburn, skin usually peels. What process best describes what has happened to the burned skin cells?

answer

apoptosis

question

Cancerous cells may not peel after a bad sunburn. What process has failed in this case?

answer

checkpoints

question

A patient has metastatic melanoma-skin cancer that has spread throughout the body. Is surgery a viable option for this patient?

answer

No. Surgery is not a viable option. Now that the cancer has spread, there is no single tumor that can be surgically removed. There are too many tumors in too many tissues to be able to remove all of them surgically.

question

Which of the following properties should a promising new ovarian cancer drug have?

answer

blocks mitosis in cancerous cells

question

Explain why chemotherapy can cause nausea, diarrhea, and hair loss.

answer

Chemotherapy interferes with all dividing cells, not just cancerous ones. Cells lining the digestive tract normally divide rapidly, and when they are affected by chemotherapy, nausea and diarrhea can occur. Similarly, cells at the base of hair follicles normally divide rapidly, and when chemotherapy drugs interfere with their division, the result is hair loss.

question

Rosa has recently been diagnosed with ovarian cancer. Tests show that her cancer has metastasized to her liver, lungs, and brain: How might have Surgery treated here cancer and would it have been feasible in Rosa's case?

answer

Surgery physically removes the cancerous cells. Once the cancer has metastasized, as in this case, surgery is not a viable option because there are now too many tumors to remove. In addition to the visible tumors, there may be many more small tumors that have established themselves in other parts of the body.

question

Rosa has recently been diagnosed with ovarian cancer. Tests show that her cancer has metastasized to her liver, lungs, and brain: How might have Radiation treated here cancer and would it have been feasible in Rosa's case?

answer

Radiation irradiates cancer cells and causes such extensive DNA damage that the cells cannot survive. Radiation is typically focused on specific location, so is not a good option in this case, given the number of distinct tumors.

question

Rosa has recently been diagnosed with ovarian cancer. Tests show that her cancer has metastasized to her liver, lungs, and brain: How might have Taxol treated here cancer and would it have been feasible in Rosa's case?

answer

Taxol interferes with the microtubules of the mitotic spindle, preventing cell division. Taxol has shown success in ovarian cancer, particularly ovarian cancer that has not responded well to other therapies.

question

Rosa has recently been diagnosed with ovarian cancer. Tests show that her cancer has metastasized to her liver, lungs, and brain: How might have Chemotherapy without Taxol treated here cancer and would it have been feasible in Rosa's case?

answer

Chemotherapy in the absence of Taxol is certainly an option. Chemotherapy drugs interfere with cell division. Different drugs have different specific mechanisms of action at the cellular level.

question

In the production of taxol: What plant was at risk from early demand?

answer

the Pacific Yew (Taxus brevifolia

question

In the production of taxol: What animal was consequently put at risk?

answer

the northern spotted owl

STUDY

A Level Biology AP Biology Cell Biology Cell Cycle In Order

AP Biology: Cancer (Loss of Cell Cycle Control) – Flashcards 10 terms

Elizabeth Hill

10 terms

Preview

AP Biology: Cancer (Loss of Cell Cycle Control) – Flashcards

question

G₁ checkpoint

answer

Stops the Cell Cycle if DNA is damaged, if so, apoptosis occurs

question

G₂ checkpoint

answer

Stops the Cell Cycle if DNA has not finished replicating or DNA is damaged

question

M (Mitosis) checkpoint

answer

Stops Mitosis if chromosomes are not properly aligned or chromosomes are not going to be distributed accurately to the daughter cells

question

Proto-oncogenes

answer

Genes that specify proteins that directly and indirectly stimulate the Cell Cycle; If mutated, they become oncogenes, or cancer causing genes

question

Oncogenes

answer

Cancer causing genes (mutated proto-oncogenes)

question

Apoptosis

answer

Often defined as programmed cell death because the cell progresses through a typical series of events that bring about its destruction

question

Cancer cells lack differentiation

answer

This means cancer cells are not specialized and do not contribute to the functioning of a tissue

question

Cancer cells have abnormal nuclei

answer

This means that the nuclei of cancer cells are enlarged and may contain an abnormal number of chromosomes

question

Cancer cells do not undergo apoptosis

answer

This means that the cancer cells do not "commit suicide" even though they are abnormal cells

question

Cancer cells form tumors

answer

This means that the cancer cells have lost all restraint and do not exhibit contact inhibition. The abnormal cancer cells pile on top of one another and grow in multiple layers, forming a tumor

STUDY

A Level Biology Biology Cell Biology Place The Following

Biology Unit 10: Cell Cycle and Cancer – Flashcards 63 terms

Charles Clay

63 terms

Preview

Biology Unit 10: Cell Cycle and Cancer – Flashcards

question

Name the 4 general phases of the cell cycle

answer

G1 Growth, S Synthesis, G2 preparation for division, and M mitosis

question

Make a statement that compares mitosis and meiosis

answer

mitosis results in the production of two genetically identical diploid cells, and meiosis results in 4 genetically varied haploid cells

question

During which phase does the size of the cell increase

answer

G1 phase

question

During which phase does the number of cells increase

answer

M phase

question

totipotent

answer

cells that are able to develop into any type of cell found in the body

question

pluripotent

answer

cells that are capable of developing into most but not all of the body's cell types

question

oncogene

answer

a type of cancer gene that normally functions to accelerate cell division and growth

question

tumor suppressor gene

answer

type of cancer gene that acts like brakes

question

DNA repair gene

answer

type of cancer gene that fixes minor damage to DNA when replicated

question

what might a mutated oncogene do?

answer

it might make cell division go and keep going on and on

question

what is required for a cell to become cancerous

answer

several genes are all mutated

question

Which four conditions activate p53 to shut down cell division?

answer

low oxygen concentration, DNA damage, chemotherapeutic agents, and other stress

question

what does p53 guard against

answer

changes to cells that might lead to tumor formation and cancer

question

What happens in G1?

answer

cells increase in size, synthesize new proteins and organelles

question

What happens in S?

answer

new DNA is synthesized

question

What happens in G2?

answer

Organelles and molecules required for cell division are produced

question

What happens in M?

answer

Cell divides to produce two daughter cells

question

What does PMAT stand for?

answer

Prophase, Metaphase, Anaphase, Telophase

question

What do internal regulators do?

answer

Allow the cell cycle to proceed only when certain events have occurred inside the cell itself (eg chromosomes have replicated)

question

What do external regulators do

answer

proteins that respond to events outside the cell and speed up or slow down the cell cycle (eg. you get a scrape, they speed up the cell cycle)

question

explain crossing over

answer

process in which homologous chromosomes exchange portions of their chromatids during meiosis

question

what is a growth factor and why is it important?

answer

An external regulatory protein that stimulates growth and division of cells, it is important because it prevents excessive cell growth

question

what is apoptosis

answer

a process of programmed cell death

question

tumor

answer

a mass of cancerous cells, can be benign(harmless) or malignant(harmful)

question

what makes Cancer cells so bad

answer

as they spread they absorb the nutrients needed by other cells, block nerve connections, and prevent the organs the invade from functioning properly

question

what are the three ways that Cancer can be treated?

answer

1. removal by surgery 2. radiation beams 3. chemotherapy

question

during which phase would you expect the amount of DNA to change

answer

synthesis phase

question

True or false: cancer risk increases with age

answer

true!

question

what are the four causes of cancer

answer

1. chemical poisons-aka mutagens 2. family history 3. radiation exposure 4. UV light

question

homologous chromosomes

answer

chromosomes in which one set comes from the male parent and one set comes from the female parent

question

diploid

answer

term used to refer to a cell that contains two sets of homologous chromosomes

question

haploid

answer

term used to refer to a cell that contains only a single set of genes, aka gamete

question

p53

answer

a gene that prevents cancer by halting the cell cycle until all chromosomes have been properly replicated

question

cell cycle

answer

a series of events cells go through as they grow and divide, results in two nearly identical daughter cells

question

3 purposes of cell division

answer

Growth Repair Asexual Reproduction

question

what are the problems associated with asexual reproduction?

answer

one disease or mutation could wipe out the entire population no genetic variation monoclonal populations are formed

question

what does cyclin do

answer

regulates a cell's progression through the cell cycle

question

what does DNA Polymerase do?

answer

it 'proofreads' the DNA for mutations or mistakes

question

chromosome

answer

form of DNA that is inherited

question

chromatin

answer

condensed or coiled chromosomes during prophase

question

chromatid

answer

on of two daughter strands of a duplicated chromosome joined by a single centromere

question

karotype

answer

picture of a whole set of chromsomes

question

sister chromatids

answer

two replicas of a single chromosome held together by a centromere after DNA replication

question

meiosis

answer

the process of creating 4 haploid sex cells with genetic variation

question

what happens in prophase

answer

Chromosomes condense. The nuclear envelope breaks down. The centrosomes move to opposite sides of the cell. The microtubules attach themselves to the sister chromatids

question

What happens in metaphase

answer

sister chromatids are lined up along the metaphase plate by the pulling on both ends

question

what happens in anaphase

answer

the sister chromatids are split in half so that the chromatids are seperated

question

what happens in telophase

answer

new nuclear envelopes form around the new sets of chromosomes

question

what happens in cytokenisis

answer

in plant cells: a cell wall forms seperating the cell into two daughter cells in animal cells: the cell membrane pinches off to form two seperate daughter cells

question

angiogenesis

answer

when the body grow a network of new blood vessels at a time of growth or repair

question

in what type of organs does meiosis occur?

answer

sex organs

question

at the end of PMAT a cell must distribute this evenly

answer

the cytoplasm

question

what do oncogenes do

answer

alter receptor molecules located on the surface of cells that are responsible for signaling the cell to divide

question

Before any cell can divide what has to happen?

answer

the DNA must be duplicated

question

what do cancerous cells have to do with angiogenesis

answer

they activate genes in healthy tissue to encourage the growth of new blood vessels into and around the cancerous tissue

question

cancer cell

answer

a cell in the body that ceases to respond to normal growth controls

question

in a cancerous cell, which stage would be the shortest?

answer

G1, growth phase

question

what type of gene is p53?

answer

a guardian gene

question

what happens when an oncogene is mutated?

answer

very rapid and ongoing cell division occurs

question

the purpose of cell division is

answer

to repair growth while maintaining the correct amount of chromosomes and DNA

question

cyclins

answer

a family of proteins involved in the progression of cells through the cell cycle

question

why is interphase the longest phase

answer

cells need time to perform their specific functions or jobs for the organismt

question

what can happen to cells if they do not divide

answer

they continue into interphase and die eventually

STUDY

A Level Biology Anatomy Anatomy And Physiology Anatomy And Physiology 2 Fluid Balance In The Body

Lymph Nodes and Lymphatic System – Flashcards 45 terms

Anthony Richie

45 terms

Preview

Lymph Nodes and Lymphatic System – Flashcards

question

What is the lymphatic system?

answer

consists of cells, tissues, and organs

question

What are circulating lymphocytes?

answer

The effector cell type of the lymphatic system essential in the immune response to harmful substances

question

What are lymphatic tissues?

answer

sites where lymphocytes proliferate, differentiate and mature

question

What are lymphatic vessels?

answer

connect parts of lyphatic system to the blood of vascular system

question

The lymphatic system monitors

answer

the body surfaces and internal body compartments and reacts to the presence of potentially harmful substances

question

What are the primary lymph organs?

answer

Thymus (T-cells) and Bone marrow (B-cells)

question

How do lymphocytes travel?

answer

via the blood vessles and lymphatic vessels to secondary lymphoid organs and tissues

question

Secondary lymphoid organs and tissues

answer

Diffuse lymphatic tissue (Gut Associated Lymphatic Tissue= GALT) Lymphatic/Lymphoid nodules and tonsils Lymph nodes Spleen

question

Th plasma cell is?

answer

Antibody producing and B cell derived

question

Small size of lymphoid nodules?

answer

Primary lymphoid nodule: consist of small lymphocytes with no germinal center

question

Macrophages are?

answer

Phagocytic cells derived from blood monocytes and antigen presenting cells

question

Large Size of lymphoid nodules?

answer

Secondary lymphoid nodule: consists of small lymphocytes in the peripheral zone and large lymphocytes located in the center called the germinal center

question

What is the germinal center?

answer

Morphological indication of lymphatic tissue response to antigen: lymphocytes activation, proliferation, and differentiation of B cells into antibody producing plasma cells

question

Lymphocytes migrate from

answer

blood to tissues and contribute to diffuse lymphatic tissue or form aggregates called lymphoid nodules `

question

B lymphocyte does what

answer

Neutralize of microbe, phagocytosis, complement activation

question

Helper T cell does what?

answer

Activation of macrophages, inflammation, activation (proliferation and differentiation) of T and B lymphocytes

question

Regulatory T lymphocyte does what?

answer

Supression of immune response

question

About what percent of lymphocytes (in blood and lymph) contribute to a circulation pool of immune cells?

answer

70%

question

What is the main type of circulating lymphocytes?

answer

T-Cells

question

Lymphocytes enter major lymphatic vessels on the right side of the body through?

answer

right lymphatic trunk

question

Lymphocytes enter major lymphatic vessels on the left side of the body through?

answer

thoracic duct

question

Afferent lymphatic vessels bring

answer

lymph to lymph node

question

What is lymph?

answer

The remaining excess fluid

question

In tissues, fluid and plasma from the blood circulation are exchanged to bring?

answer

nutrients to cells and eliminate the waste

question

Lymph is an ultra- filtrate of the blood, rich in various?

answer

proteins, antigens, and lymphocytes and drains to lymph nodes

question

Why do lymphs maintain a unidirectional flow?

answer

Due to the action of valves and smooth muscles on the walls of lymphatic vessels

question

Lymph enters via the afferent lymphatic vessels, to subscapsular sinuses, precorlates through the tissue of lymph node and exits the

answer

efferent lymphatic vessel

question

The inner cortex contains the

answer

T-cell zones

question

Where does lymph travel and get filtrated?

answer

Compose of capsule, cortex, medulla, and sinuses ( subscapular, trabecular, and medullary)

question

B-cells in lymphoid nodules are found in the

answer

outer cortex

question

What cells are in lymphatic tissue?

answer

Reticular Cells (Collagen type III)

question

How does lymphatic spread?

answer

biopsy of sentinel lymph nodes, vascular spread, transcoelomic spread (body cavities)

question

What initially stops tumor spread regionally?

answer

Lymph Nodes

question

What happens to tumor cells in the lymph nodes?

answer

Some are arrested and destroyed, other are drained in lymphatic drainage

question

What is lymphangiogenesis and what happens prior to metastasis?

answer

formation of new lymphatic vessels, is induced prior to metastasis to next lymph nodes

question

Growth of metastatic tumor cells inside lymph nodes leads to

answer

lymphatic dysfunction, rerouting of lymph flow and metastasis to next lymph nodes

question

What is associated with lymph node metastasis?

answer

Increased lymphatic flow, dilation of collecting vessels

question

What is Sentinel lymph nodes?

answer

first node to receive drainage from the tumor area

question

Metastasizing cancer cells leaving the tumor are most likely to collect in the

answer

Sentinel lymph nodes

question

Which way would PTC cancer cells enter the next lymph node during lymphatic spread if this patient was not treated promptly?

answer

Afferent lymphatic vessels

question

Which of the following connective tissue or connective tissue element known to form mesh like network within the lymph nodes was most likely involved in the process of filtration and trapping of the PTC tumor cells allowing the immune system of this patient to target these cells?

answer

Reticular Fibers

question

Which of the following is an area in the lymph node predominantly occupied by T-cells?

answer

Deep Cortex

question

Which of the following statements is true about lymphoid nodule?

answer

found in lymph node

question

Lymph drains from the lymph nodes via

answer

efferent lymphatics and joins the blood circulation

question

Lymph Nodes contain lymphioid nodules mostly with

answer

B-Cells in outer and T cells in inner

STUDY

A Level Biology Abo Blood Group Antigens Cell Biology

Biology Unit 5 Chapter 16 – DNA Technology – Flashcards 95 terms

Daphne Armenta

95 terms

Preview

Biology Unit 5 Chapter 16 – DNA Technology – Flashcards

question

(Refer to exam q) Gene therapy is used to treat the genetic disorder,ADA deficiency. Affected individuals are unable to produce the enzyme adenosine deaminase (ADA). Without this enzyme, T lymphocytes, a type of white blood cell, cannot provide immunity to infection. The diagram shows the processes involved in the treatment of ADA deficiency by gene therapy. What is meant by gene therapy? (1)

answer

Replacement of defective gene

question

The ADA gene is inserted into a virus. Give two advantages of using a virus in gene therapy. (2)

answer

Can inject DNA into cells; Targets specific cells

question

Individuals who have been treated by this method of gene therapy do not pass on the ADA gene to their children. Explain why. (1)

answer

Gamete cells do not contain ADA gene

question

T lymphocytes are produced in bone marrow. A bone marrow transplant from a genetically matched donor can provide a permanent cure for ADA deficiency. Suggest why bone marrow for a transplant is obtained from a genetically matched donor. (1)

answer

To prevent immune response

question

Explain why treatment of ADA deficiency by gene therapy must be repeated at regular intervals, whereas a single bone marrow transplant can provide a permanent cure. (2)

answer

T lymphocytes have a limited life span; bone marrow provides continual supply of T lymphocytes

question

(Refer to exam q) The polymerase chain reaction is a process which can be carried out in a laboratory to replicate DNA. The diagram shows the main stages involved in the polymerase chain reaction. Explain why DNA is heated to 95 °C. (1)

answer

To separate the two strands

question

What is the role of a primer in this process? (1)

answer

Enables sequencing to start

question

What is the role of DNA polymerase? (1)

answer

Joins DNA nucleotides

question

How many DNA molecules will have been produced from one molecule of DNA after 6 complete cycles? (1)

answer

question

Suggest one use of the polymerase chain reaction. (1)

answer

Replication of DNA from crime scene

question

Give two ways in which the polymerase chain reaction differs from the process of transcription. (2)

answer

Transcription uses RNA polymerase; and one template strand whereas PCR uses both strands

question

Research scientists can increase the nutritional value of potatoes by genetically engineering potato plants. A gene which results in increased protein production has been removed from cells of an amaranth plant and inserted into cells of a potato plant. Describe how a gene could be removed from cells of an amaranth plant and inserted into cells of a potato plant. (6)

answer

Cut out gene using an endonuclease; The endonuclease cuts a DNA double strand at a specific sequence of bases called a recognition site; Use the same enzyme to cut; a plasmid; The complementary bases are fixed by the enzyme DNA ligase; The vector is then introduced to the plant cell by a harmless virus injecting the DNA

question

Plasmids are often used as vectors in genetic engineering. What is the role of a vector? (1)

answer

Transfer genes from one organism to another

question

Describe the role of restriction endonucleases in the formation of plasmids that contain donor DNA. (2)

answer

Cut open plasmid; Cut donor DNA, to remove gene

question

Describe the role of DNA ligase in the production of plasmids containing donor DNA. (1)

answer

Backbones joined

question

(Refer to exam q) There are many different restriction endonucleases. Each type cuts the DNA of a plasmid at a specific base sequence called a restriction site. The diagram shows the position of four restriction sites, J, K, L and M, for four different enzymes on a single plasmid. The distances between these sites is measured in kilobases of DNA. The plasmid was cut using only two restriction endonucleases. The resulting fragments were separated by gel electrophoresis. The positions of the fragments are shown in the chart below. Which of the restriction sites were cut? Explain your answer. (2)

answer

L and M; The length of the fragments were 64 and 36 kilobases

question

The polymerase chain reaction (PCR) can be used to produce large quantities of DNA. Describe how the PCR is carried out. (6)

answer

DNA heated to 90 - 95°C; causing the strands to separate; It is then cooled to 55°C which causes primers to bind; Temperature increased to 72°C and the nucleotides attach to the strand; by complementary base pairing; DNA polymerase joins the nucleotides together

question

About twenty percent of the DNA produced by the PCR is copied inaccurately. Suggest and explain why it is not safe to use the PCR to clone the CFTR gene for use in treating cystic fibrosis. (4)

answer

The percentage risk is too high for human application; If the sequence of amino acids changes; A non-functional protein may be produced; Which will be harmful

question

(Refer to exam q) One technique used to determine the sequence of nucleotides in a sample of DNA is the Sanger procedure. This requires four sequencing reactions to be carried out at the same time. The sequencing reactions occur in four separate tubes. Each tube contains • a large quantity of the sample DNA • a large quantity of the four nucleotides containing thymine, cytosine, guanine and adenine • DNA polymerase • radioactive primers A modified nucleotide is also added to each tube, as shown in Figure 1. A large quantity of the DNA sample is required for this procedure. Name the reaction used to amplify small amounts of DNA into quantities large enough for this procedure. (1)

answer

Polymerase chain reaction

question

Explain the reason for adding each of the following to the tubes. (i) DNA polymerase (ii) Primers (2)

answer

(i) Joins nucleotide together; (ii) Enables sequencing to start

question

When a modified nucleotide is used to form a complementary DNA strand, the sequencing reaction is terminated. Suggest how this sequencing reaction is terminated. (1)

answer

Modified nucleotide does not fit DNA polymerase

question

A sample of DNA analysed by this technique had the following nucleotide base sequence. T G G T C A C G A Give the base sequence of the shortest DNA fragment which would be produced in Tube 2. (1)

answer

question

(Refer to exam q) A different sample of DNA was then analysed. The DNA fragments from the four tubes were separated in a gel by electrophoresis and analysed by autoradiography. Figure 2 shows the banding pattern produced. Explain why the DNA fragments move different distances in the gel. (1)

answer

Different lengths

question

What makes the DNA fragments visible on the autoradiograph? (1)

answer

Radioactive primer

question

Use Figure 2 to determine the sequence of nucleotides in this sample of DNA. (1)

answer

GAAGTCTCAG

question

Explain how the presence of an altered protein in people with cystic fibrosis results in the production of very thick and sticky mucus, and how this accounts for the symptoms of this disorder. (5)

answer

CFTR; blocks outward passage of chloride ions; so water is retained in the cell; Therefore mucus is unable to be removed in the lungs so infection is more likely; Mucus causes narrowing of air passages so breathing is more difficult

question

(Refer to BYB2 June 2005 paper) Cystic fibrosis can be caused by any one of several mutant alleles of the cystic fibrosis gene. The most common of these mutant alleles accounts for about 70% of cases of cystic fibrosis. The use of gene probes can identify individuals carrying this allele. Gene probes are single strands of DNA which are radioactively labelled. They have a base sequence that is complementary to a mutant allele. The main stages in using a gene probe are shown in the diagram. Using the information given, explain how the use of a gene probe could enable the presence of a mutant allele of the cystic fibrosis gene to be detected. (4)

answer

Probe will attach to the mutant allele; It only attaches to one DNA strand; as a result of complementary base pairing; This is radioactivity detected on film if the mutant allele is present

question

Sheep have been genetically engineered to produce alpha-1-antitrypsin which is used to treat cystic fibrosis. Use your knowledge of this process to explain one argument for and one against using sheep in this way. (2)

answer

For: The gene is only active in mammary cells; Against: Long term effects not known

question

A strain of rice called 'golden rice' has been genetically modified to carry an extra gene. Golden rice produces more vitamin A than ordinary rice. Describe how this extra gene could be introduced into a cell of a rice plant. (1)

answer

Use of vector

question

When genes are introduced into cells, antibiotic resistance genes are often added as well. Explain the reason for this. (2)

answer

Acts as a marker gene; Allows identification of cells with the new gene

question

Some scientists are concerned about the use of antibiotic resistance genes in genetic engineering. Suggest why. (2)

answer

May pass to bacteria; Pathogens may become resistant and unable to treat disease

question

(Refer to exam q) Use information in the passage and your own biological knowledge to answer the questions. Describe how genetic fingerprinting may be carried out on a sample of panda DNA. (7)

answer

DNA is cut using restriction endonucleases; Gel electrophoresis is used; To separate DNA fragments according to length; These are transferred to a nylon membrane; DNA probe is applied; To radioactively label the DNA; The membrane is placed onto an X-ray film which is exposed

question

Explain how genetic fingerprinting allows scientists to identify the father of a particular panda cub. (2)

answer

All bands in cub which dont come from mother; Must be in fathers DNA fingerprint

question

When pandas are bred in zoos, it is important to ensure only unrelated pandas breed. Suggest how genetic fingerprints might be used to do this. (1)

answer

Select pairs with dissimilar DNA fingerprints

question

Suggest why panda DNA is found in faeces. (1)

answer

Cells from panda are in faeces

question

Explain why the PCR is carried out on the DNA from the faeces. (1)

answer

To increase amount of DNA

question

Explain why the primers used in the PCR will bind to panda DNA, but not to DNA from bacteria or bamboo. (2)

answer

DNA has a specific base-sequence; Primers bind to DNA by complementary base-pairing

question

DNA from wild pandas could also be obtained from blood samples. Suggest two advantages of using faeces, rather than blood samples, to obtain DNA from pandas. (2)

answer

Taking samples from animals causes stress to animal; Pandas are a threat to humans

question

(Refer to June 2010 paper) There are wolves in many European countries. Scientists investigated the genetic diversity of these wolves. They collected samples of DNA from the mitochondria of wolves from different countries. For each sample they identified which haplotypes were present in the DNA. A haplotype is a particular sequence of bases on DNA. Mutations can produce new haplotypes. The scientists wanted to find out whether one of the haplotypes in the Portuguese wolves was the same as one of those in the Spanish wolves. They used a restriction endonuclease, electrophoresis and a labelled DNA probe. For what purpose did they use (i) the restriction endonuclease (ii) electrophoresis?

answer

(i) To cut the DNA (ii) To separate the pieces of DNA

question

Explain why the labelled DNA probe could be used to find out whether the haplotypes were the same. (2)

answer

Complimentary base sequence; You would see if it binds to both haplotypes

question

(Refer to June 2011 paper) Scientists used restriction mapping to investigate some aspects of the base sequence of an unknown piece of DNA. This piece of DNA was 3 000 base pairs (bp) long. The scientists took plasmids that had one restriction site for the enzyme Kpn1 and one restriction site for the enzyme BamH1. They inserted copies of the unknown piece of DNA into the plasmids. This produced recombinant plasmids. The diagram shows a recombinant plasmid. When the scientists digested one of the recombinant plasmids with Kpn1, they obtained two fragments. One fragment was measured as 1 000 bp. The other fragment was described as "very large". What does this show about the base sequence of the unknown piece of DNA? (2)

answer

It has the restriction site cut by Kpn1; Once

question

One of the fragments that the scientists obtained was described as "very large". What is represented by this very large fragment? (1)

answer

Most of plasmid and the rest of the unknown DNA

question

When the scientists digested another of the recombinant plasmids with BamH1, they obtained three fragments. How many BamH1 restriction sites are there in the unknown piece of DNA? (1)

answer

question

Scientists need to take precautions when they carry out restriction mapping. They need to make sure that the enzyme they have used has completely digested the DNA. One check they may carry out is to add the sizes of the fragments together. How could scientists use this information to show that the DNA has not been completely digested? Explain your answer. (2)

answer

Large pieces of DNA present; Add up to more than the total length of original DNA

question

(Refer to June 2012 paper) Haemophilia is a genetic condition in which blood fails to clot. Factor IX is a protein used to treat haemophilia. Sheep can be genetically engineered to produce Factor IX in the milk produced by their mammary glands. The diagram shows the stages involved in this process. Name the type of enzyme that is used to cut the gene for Factor IX from human DNA (Stage 1) . (1)

answer

Endonuclease

question

The jellyfish gene attached to the human Factor IX gene (Stage 2) codes for a protein that glows green under fluorescent light. Explain the purpose of attaching this gene. (2)

answer

Acts as a marker gene; Shows that the human gene has been taken up

question

The promoter DNA from sheep (Stage 3) causes transcription of genes coding for proteins found in sheep milk. Suggest the advantage of using this promoter DNA. (2)

answer

Factor IX present in milk; Do not need to kill sheep to obtain Factor IX

question

Many attempts to produce transgenic animals have failed. Very few live births result from the many embryos that are implanted. Suggest one reason why very few live births result from the many embryos that are implanted. (2)

answer

Embryo is foreign; Embryo is attacked by immune system

question

It is important that scientists still report the results from failed attempts to produce transgenic animals. Explain why. (2)

answer

Saves time and money for others; Prevents the same errors from being made

question

(Refer to June 2012 paper) Huntington's disease is a genetic condition that leads to a loss in brain function. The gene involved contains a section of DNA with many repeats of the base sequence CAG. The number of these repeats determines whether or not an allele of this gene will cause Huntington's disease. Scientists took DNA samples from three people, J, K and L. They used the polymerase chain reaction (PCR) to produce many copies of the piece of DNA containing the CAG repeats obtained from each person. They separated the DNA fragments by gel electrophoresis. A radioactively labelled probe was then used to detect the fragments. The diagram shows the appearance of part of the gel after an X-ray was taken. The bands show the DNA fragments that contain the CAG repeats. Only one of these people tested positive for Huntington's disease. Which person was this? Explain your answer. (2)

answer

Person K; As has band that travelled the shortest distance so has largest fragment and therefore highest number of CAG repeats

question

The diagram only shows part of the gel. Suggest how the scientists found the number of CAG repeats in the bands shown on the gel. (1)

answer

Run fragments of known length at the same time

question

Two bands are usually seen for each person tested. Suggest why only one band was seen for Person L. (1)

answer

CAG fragments are the same length

question

How is complementary DNA made using reverse transcriptase? (4)

answer

A cell that readily produces the required protein is selected; The relevant mRNA is extracted; mRNA acts as a template on which a complementary single-stranded copy of DNA is formed using reverse transcriptase; DNA polymerase joins complementary free nucleotides onto the single DNA strand; Forms a double-stranded DNA molecule with the required gene

question

What are the two ways in which DNA fragments can be cloned? (2)

answer

In vivo, transferring the fragments to a host cell using a vector; In vitro, using the polymerase chain reaction

question

Describe how a gene can be inserted into a vector by using restriction endonucleases. (5)

answer

Restriction endonucleases cut DNA at recognition site; A plasmid is cut at its gene for antibiotic resistance using the same restriction endonuclease; The sticky ends of the DNA fragments are complementary to the sticky ends of the cut plasmid; DNA fragments and open vectors are mixed with DNA ligase; Ligase joins the phosphate-sugar frameworks together

question

What is the role of a vector in in vivo cloning? (1)

answer

Transfers DNA from one organism into another

question

When plasmids are reintroduced into bacterial cells, not all the bacterial cells will possess the desired DNA fragments. Suggest the two main reasons for this. (2)

answer

Only a few bacterial cells take up the plasmids when they are mixed together; Some plasmids will have closed up without incorporating the DNA fragment

question

How are plasmids reintroduced into bacterial cells? (2)

answer

They are mixed together in a medium containing calcium ions; Calcium ions and temperature changes make the bacteria permeable to the plasmids

question

How can you find out which bacterial cells have taken up the plasmids? (4)

answer

Bacterial cells are grown on a medium that contains an antibiotic; Bacterial cells that have taken up the plasmids will have acquired the gene for resistance of the antibiotic; These bacterial cells are able to break down the antibiotic and survive; Cells that have not taken up the plamid will not be resistant to antibiotic and die

question

How are antibiotic-resistance markers used to find out which bacterial cells have taken up the desired gene? (6)

answer

The bacterial cells that survived the treatment with the first antibiotic took up the plasmid; These cells are grown on an agar plate in colonies; A sample of each colony is tranferred onto a replica agar plate in exactly the same position on the plate as the original colonies; The replica plate contains the second antibiotic; The colonies killed by the antibiotic are the ones that have taken up the required gene; These colonies are located on the original plate

question

Why are the bacterial cells that are killed by the second antibiotic the cells that have taken up the desired gene? (2)

answer

Because the antibiotic resistance gene was cut to incorporate the desired gene; So no longer produces the enzyme that breaks down the second antibiotic

question

Why are gene markers necessary during in vivo cloning? (1)

answer

To show which cells have taken up the desired gene

question

Give one advantage of using fluorescent gene markers rather than antibiotic gene markers. Explain your answer. (3)

answer

Results can be obtained more easily and quickly; With antibiotic gene markers, replica plating is necessary because the cells with the required gene are killed; With fluorescent markers, the cells are not killed so replica plating is unnecessary

question

Suggest two advantages of in vitro gene cloning. (2)

answer

Extremely rapid, useful when there is a minute amount of DNA available, e.g. at a crime scene, so no loss of time; Does not require living cells, only a DNA base sequence

question

Suggest two advantages of in vivo gene cloning. (2)

answer

Useful in introducing a gene into another organism through its use of vectors; No risk of contamination due to the specific complementary sticky ends created by restriction endonucleases

question

State three ways in which genetic modification of organisms has benefited humans? (3)

answer

Increased the yield from animals and crop plants; Improved nutrient content of foods; Produced vaccines

question

How have tomatoes been genetically modified to prevent softening? (4)

answer

Insertion of a gene; which has a complementary base sequence to the gene which produces the softening enzyme; The two mRNA strands join, preventing the mRNA from the original gene being translated; Softening enzyme therefore not produced

question

Suggest one benefit and one disadvantage of using genetically modified herbicide-resistant crop plants together with the relevant herbicide. Explain your answer. (2)

answer

Advantage: Crop yield is greater because the herbicide kills the weeds that are competing for light, water and minerals but not the crop; Disadvantage: The herbicide might accumulate further up in the food chain and might be toxic to other organisms

question

Suggest four advantages of recombinant DNA technology. (4)

answer

Microorganisms can be modified to produce a range of substances, e.g. antibiotics, hormones and enzymes, that are used to treat disease; Genetically modified crops can be modified to make them more tolerant to environmental extremes, so they can be grown in various places; Gene therapy can be used to cure certain genetic disorders, such as cystic fibrosis; Genetically modified animals can be modified to increase the yield of milk, meat etc.

question

Suggest four risks of recombinant DNA technology. (4)

answer

Is the cost of genetic engineering justified, or would the money be better used to fight hunger and poverty?; The ability to manipulate genes may get into the wrong hands, so individuals, groups or goverments may use this to achieve power; Unsure of long-term consequences; Reduced genetic variety and biodiversity

question

What is the cause of cystic fibrosis? (2)

answer

Mutant recessive allele; Deletion mutation in which A-A-A are missing

question

What is cystic fibrosis? (5)

answer

Deletion mutation causes an amino acid to be left out of the CFTR protein; Tertiary structure of protein changes; Protein unable to trasport chloride ions across epithelial membrane; So water does not leave cell into mucus layer by osmosis; Resulting in sticky mucus

question

In which two ways may gene therapy be used to treat cystic fibrosis? (2)

answer

Gene replacement - replacing defective gene with healthy gene; Gene supplementation - healthy gene added alongside defective gene, which is dominant so masks effects of the recessive allele

question

What is the difference between germ-line and somatic-cell gene therapy? (4)

answer

Germ-line: Involves replacing/supplementing the defective gene in the fertilised egg; Ensures that all cells, as well as cells of offspring, will develop normally; Somatic-cell: Targets just affected tissues; Treatment needs to be repeated periodically as cells are constantly dying

question

How is the normal CFTR gene introduced into a cystic fibrosis sufferer through somatic-cell gene therapy using a harmless virus? (5)

answer

Adenovirus made harmless by interfering with a gene involved in their replication; Adenovirus grown in epithelial cells, along with plasmids that contain the normal CFTR gene; CFTR gene becomes incorporated into the DNA of the adenovirus; Adenovirus isolated from epithelial cells and purified; Adenovirus introduced into nostrils of patient and inject their DNA into the epithelial cells of the lungs

question

How is the normal CFTR gene introduced into a cystic fibrosis sufferer through somatic-cell gene therapy using lipid molecules? (5)

answer

CFTR genes isolated from tissue and inserted into plasmids; Plasmids reintroduced into bacterial cells and gene markers are used to detect which bacteria have taken up plasmids with gene; Bacteria cloned; Plasmids extracted from bacteria and wrapped in lipid molecules to form liposomes; Liposomes sprayed into nostrils and pass across phospholipid bilayer of epithelial cell-surface membranes

question

Why are these methods not always effective? (3)

answer

Even when gene is successfully delivered to epithelial cells, very few are expressed; The gene and the vector may cause an immune response so it is often rejected; Effect is short-lived because somatic cells are not passed onto offspring and die so need to be replaced

question

Explain how two parents, neither of whom suffers from cystic fibrosis, might have a child with the disease. (3)

answer

If both parents are heterozygous for the CFTR gene, then each would carry one dominant and one recessive allele; They would not suffer as they have the dominant allele; If an offspring inherits one recessive allele from each parent, they would suffer from CF

question

What are the two types of DNA probes? (2)

answer

Radioactively labelled probes; Fluorescently labelled probes

question

How are DNA probes used to locate specific genes? (4)

answer

DNA probe has bases that are complementary to the portion of DNA sequence that makes up the required gene; DNA strands are separated; Separated DNA strands and probe are mixed in DNA hybridisation, and probes join to complementary DNA bases; The site at which the probe binds is identified by its radioactivity/fluorescence

question

How can the exact order of nucleotides on a strand of DNA be determined? (6)

answer

Set up four test tubes, each containing single-stranded fragments of DNA to be sequenced, a labelled primer, nucleotides, one of four terminator nucleotides and DNA polymerase; The DNA fragments in each test tube will vary in length but will all end with a nucleotide that has the same base; The fragment lengths are separated using gel electrophoresis; The fragments are placed onto agar gel and a voltage is applied; The larger the fragments the more slowly they move; Photographic film is placed over the gel and is exposed by the radioactivity of each DNA fragment

question

What is a DNA probe? (2)

answer

A short, single-stranded section of DNA; that has a label attached to make it easily identifiable

question

State two roles of a primer used in the Sanger method of sequencing of DNA. (2)

answer

Starts the process of DNA synthesis by making the DNA double-stranded; Carries the radioactive label for later identification of the DNA fragment produced

question

Describe the process of genetic screening. (7)

answer

The order of nucleotides on the mutated gene is determined by DNA sequencing; A fragment of DNA with complementary bases to the mutated gene is produced; A DNA probe is formed by radioactively labelling the DNA fragment; PCR used to produce more copies of the DNA probe; Probe added to single-stranded DNA fragments from individual; If the donor has mutated gene, some of their DNA fragments will have a complementary base sequence to the probe and they will join; DNA fragments will be labelled and can be distinguished by exposing X-ray film

question

What information is given in genetic counselling? (3)

answer

Advice on how likely it is that a certain disease will arise in parents' offspring; The emotional, psychological, economic and social consequences of a disease; The best course of treatment

question

mRNA can be converted to cDNA. Name the enzyme used in this process. (1)

answer

Reverse transcriptase

question

(Refer to June 2013 paper) The diagram shows the base sequence on DNA where a restriction endonuclease cuts DNA. Use evidence from the diagram to explain what is meant by a palindromic recognition sequence on DNA. (1)

answer

GGATCC same as CCTAGG in opposite direction

question

(Refer to June 2013 paper) A husband and wife wanted to know whether they were carriers of the mutated form of a gene. This mutation is a deletion that causes a serious inherited genetic disorder in people who are homozygous. A geneticist took samples of DNA from the husband and the wife. He used a DNA probe to look for the deletion mutation. The DNA probe was specific to a particular base sequence in an exon in the gene. Exons are the coding sequences in a gene. The geneticist compared the couple's DNA with that of a person known not to carry this mutation. The chart shows the geneticist's results. The geneticist told the couple they were both carriers of the mutated gene. Explain how he reached this conclusion. (3)

answer

Carriers are heterozygous; Both have DNA that binds to about half of the amount of probe that non-carrier does; Probe binds to healthy allele

question

The DNA probe the geneticist used was for an exon in the DNA, not an intron. Explain why. (3)

answer

Introns are not translated; Introns do not code for amino acids; Mutations of only exons affect amino acid sequences

question

To make the DNA probe, the geneticist had to find the base sequence of the normal gene. Once he had copies of the gene, what methods would he use to find the base sequence of the gene? (2)

answer

Restriction mapping; Sanger method

question

(Refer to June 2013 paper) Some species of crop plant produce a substance called glycinebetaine (GB). Scientists transferred the gene for GB into a species of crop plant that does not normally produce GB. These genetically modified plants then produced GB. The scientists grew large numbers of the same crop plant with and without the gene at different temperatures. After 3 days, they found the increase in dry mass of the plants. Figure 1 shows their results. Describe the effect on growth of transferring the gene for GB into this plant. (2)

answer

No effect at 25 degrees; Keeps growing up to 35 degrees, more than without GB

question

The scientists measured the rate of photosynthesis in plants that produce GB and plants that do not produce GB at 25 ºC, 35 ºC and 45 ºC. The scientists concluded that the production of GB protects photosynthesis from damage by high temperatures. Use these data to support this conclusion. (1)

answer

Significantly different - standard errors do not overlap

question

Use the data from Figure 2 for plants that do not produce GB to explain the effect of temperature on changes in dry mass of the plants shown in Figure 1. (4)

answer

Some enzymes denatured; Less photosynthesis, so fewer sugars formed; Less respiration; Less ATP for growth

question

The scientists' hypothesis at the start of the investigation was that crop plants genetically engineered to produce GB would become more resistant to high environmental temperatures. The scientists developed this hypothesis on the basis of previous research on crops that are grown in hot climates. Suggest how the scientists arrived at their hypothesis. (2)

answer

Crop plants cited in this research make GB; So assumed making plants produce GB makes them resistant to high temperatures

question

Scientists can separate fragments of DNA using electrophoresis. Suggest how they can use electrophoresis to estimate the number of base pairs in the separated fragments. (2)

answer

Smaller fragments move further; Compare with distance moved by fragments of known size

STUDY

A Level Biology AP Biology Least Squares Regression Line Make Good Use Of Probability Related Health Problems Statistics Strong Positive Correlation

My Phlebotomy – Flashcards 86 terms

Stephanie Landry

86 terms

Preview

My Phlebotomy – Flashcards

question

A quantitative test will have units attached to numeric values. True or False

answer

True

question

Physical hazards in the laboratory can be classified as electrical, fire, or mechanical. True or False

answer

TRUE

question

Laboratories that perform moderate-complexity tests are required to submit to unannounced inspection every 2 years. True or False

answer

TRUE

question

When using a fire safety blanket, be sure to wrap the person securely in the blanket to smother the flames. True or False

answer

FALSE

question

The most effective means of preventing infection is the use of latex gloves. True or False

answer

FALSE

question

The gram is the unit of mass in the metric system. True or False

answer

TRUE

question

The longer the objective of the microscope, the greater the magnification of the lens. True or False

answer

TRUE

question

A centrifuge load always contains an even number of tubes. True or False

answer

TRUE

question

The Red & Gray marbled topped vacutainer tube contains silica particles to enhance clotting and a thixotropic gel to assist in the separation of serum and blood cells. True or False

answer

TRUE

question

Concerning venipuncture needles, the smaller the gauge, the larger the lumen of the needle. True or False

answer

TRUE

question

The smaller the gauge of the venipuncture needle, the less likely that hemolysis of blood cells will occur. True or False

answer

TRUE

question

The NCCLS has recommended the drawing of red topped "waste" tube before darwing a light blue topped vacutainer tube thromboplastin released from cells during the venipuncture can interfere with coagulation testing. True or False

answer

TRUE

question

When drawing a venous blood sample from the hand, a tourniquet should never be used. True or False

answer

False

question

Capillary blood is a mixture of arterial blood and venous blood. True or False

answer

TRUE

question

During insertion of the needle into the vein during a routine venipuncture, the bevel of the needle should be facing down. True or False

answer

FALSE

question

While one is obtaining capillary blood, it is important to squeeze and milk the finger to obtain an aqequate amount of blood. True or False

answer

TRUE

question

According to the American Society of Clinical Pathologists, nearly 80% of physicians decisions are based on laboratory testing. True or False

answer

TRUE

question

The tourniquet should be tied no longer than 5 minutes. True or False

answer

FALSE

question

Rubbing alcohol is commonly used too prevent infection during venipuncture. True or False

answer

TRUE

question

Needles used during venipuncture may be only used once. True or False

answer

TRUE

question

A portion of a well-mixed sample removed for testing is called: Aliquot

answer

Aliquot

question

A term used to describe a blood sample in which the red blood cells have ruptured is referred to. Hemolyzed

answer

Hemolyzed

question

Decreased hemoglobin levels are seen in which of the following illnesses: Iron-deficiency Anemia & Cirrhosis of the Liver

answer

Iron-deficiency Anemia / Cirrhosis of the Liver

question

Involves the study of bacteria, fungi, yeasts, parasites, and viruses: Microbiology

answer

Microbiology

question

The act passed by Congress to established quality standards for all laboratory testing is referred to as: Clinical Laboratory Improvement Amendments CLIA

answer

Clinical Laboratory Improvement Amendments CLIA

question

Catergories to tests performed in the clinical laboratory are assigned by the FDA on the basis of the: Potential risk to public health

answer

Potential risk to public health

question

Laboratory tests performed in a physican's office are most likely to be categorized as: Waived and Moderate-Complexity

answer

Waived and Moderate-Complexity

question

What is not considered a waived test: Gram staining

answer

Gram staining

question

A blood culture and sensitivity (C&S) test is most likely performed in which division of the clinical laboratory: Microbiology

answer

Microbiology

question

In the identification system of the National Fire Protection Association, the White Diamond indicates: Special hazards of the chemical

answer

Special hazards of the chemical

question

Which of the following is least likely to prevent the spread of infection in a laboratory: Using sterile cups in urine collection

answer

Using sterile cups in urine collection

question

The pledge of healthcare professionals to work to achieve the highest degree of excellence in the care given to every patient is otherwise known as: Quality Assurance

answer

Quality Assurance

question

The most common temperature for an incubator in the microbiology laboratory is: 37 degrees celisus

answer

37 celisus

question

Pipets used to prepare reagents include: Graduated and Volumetric

answer

Graduated and Volumetric

question

Which of the following is most accurate to measure 500 mL: 500 mL Volumetric flask

answer

500 mL Volumetric flask

question

The ocular of the microscope generally magnifies an image: 10 x or 10 times bigger

answer

10 times

question

The microscope component that directs the light up through the stages is the: Condenser

answer

Condenser

question

When the 40x objective is in place on the microscope, the total magnification of the specimen is: 400 x or 400 times bigger

answer

400x

question

Immersion oil can used on what objective lense of a microscope: 100 x or 100 times

answer

100x 100 times

question

A centifuge is used to separate: Liquids from solids, Blood cells from serum or plasma, and crystals from urine.

answer

A centifuge is used to separate: Liquids from solids, Blood cells from serum or plasma, and crystals from urine.

question

Preventing aerosolization in a centifuge can be accomplished by ensuring that: The tubes are tightly capped.

answer

The tubes are tightly capped.

question

An autoclave can best be compared to an: Pressure cooker

answer

Pressure cooker

question

The word autoclaved appears on special tape used in an autoclave only if the temperature has reached: 121 degrees celsus

answer

121 degrees celsus

question

What tube is used routinely for Hematology testing: Lavender Topped

answer

Lavender Topped

question

No anticoagulants are found in which tube: Red Topped

answer

Red Topped

question

If a laboratory test requires serum, which tube is the tube of choice: Red Topped

answer

Red topped

question

For collection of blood specimens during a glucose tolerance test which type of tube is used: Gray Topped

answer

Gary Topped

question

Name the anticoagulant that prevents platelets from clumping and preserves the appearance of blood cells for microscopic preparation: Ethylenediamine tetraacetic acid or EDTA

answer

Ethylenediamine tetraacetic acid or EDTA

question

The slant at the open end of a needle used for venipuncture is termed: The Bevel

answer

bevel

question

The needle size most commonly used for adult venipuncture is: 21 gauge

answer

21 gauge

question

The needle size most commonly used by the blood bank for donations is: 16 gauge

answer

16 gauge

question

The needle size most commonly used on infants or elderly patients is: 23 gauge

answer

23 gauge

question

Plasma could be retrieved from what tube or tubes: LAVENDER AND GRAY TUBES

answer

LAVENDER AND GRAY TUBES

question

A tourniquet is used during the phlebotomy procedure to: Prevent venous flow out of the site & Cause the vein to bulge.

answer

Prevent venous flow out of the site & Cause the vein to bulge

question

A tourniquet should remain tied on a patient's arm no longer than: 1 minute

answer

1 minute

question

Without a clot activator, whole blood typically clots in: 30 to 60 minutes

answer

30 to 60 minutes

question

Thixotrpoic gel, found in the SST red and gray marbled-topped vacutainer tube: Is less dense than red blood cells but more dense than serum.

answer

Is less dense than red blood cells but more dense than serum.

question

The portion of the venipuncture needle that fits into the syringe or vacutainer adapter: The Hub The Hub

answer

The Hub

question

A syringe is preferred over a vacutainer collection when: The patient's veins are fragile, and the sample must be drawn from the hand veins.

answer

The patient's veins are fragile, and the sample must be drawn from the hand veins.

question

Leaving a tourniquet tied on a patient's arm for longer than the recommended time results in: Bifurcation Bifurcation

answer

Bifurcation

question

Before a routine venipuncture or capillary puncture, the site is typlically cleaned with: 70% Isopropyl Alcohol 70% Isopropyl Alcohol

answer

70 % Isopropyl Alcohol

question

With a routine venipuncture, the angle in which the needle enters the arm should be how many degrees? 15 to 30 degrees 15 to 30 degrees

answer

15 to 30

question

During a routine venipuncture, when should the phlebotomist request that the patient "make a fist": After applying the tourniquet and before inserting the needle.

answer

After applying the tourniquet and before inserting the needle.

question

During a routine venipuncture, when should the phlebotomist request that the patient "release the fist": When the blood enters the first tube being drawn.

answer

When the blood enters the first tube being drawn.

question

During a routine venipuncture, when is the correct time to remove the tourniquet: As the last tube to be drawn begins to fill.

answer

As the last tube to be drawn begins to fill.

question

The veins that can be used for routine venipuncture are? Median Cephalic vein, Median Basilic vein, and Supplementary cephalic vein

answer

Median Cephalic vein, Median Basilic vein, and Supplementary cephalic vein

question

A winged infusion set is also known as a: Butterfly needle Butterfly needle

answer

Butterfly needle

question

A needlestick is more likely to happen if: An attempt is made to recap a needle.

answer

An attempt is made to recap a needle.

question

A hematoma can be caused by: Excessive probing to locate a vein, Failure to insert the needle far enough into the vein, and if the needle is penetrating all the way through a vein.

answer

Excessive probing to locate a vein, Failure to insert the needle far enough into the vein, and if the needle is penetrating all the way through a vein.

question

The device used for dermal puncture is a: Lancet Lancet

answer

Lancet

question

The Order of draw is as follows: BLOOD CULTURE BOTTLES OR YELLOW LIGHT BLUE TUBE RED OR GOLD TUBE GREEN TUBE LAVENDER TUBE PINK TUBE GRAY TUBE

answer

...

question

The Light Blue tube contains which additive: NA CITRATE OR SODIUM CITRATE

answer

...

question

THE RED TUBE IS CONTAINS NO ADDITIVE BUT IS USED FOR: SERUM SERUM

answer

...

question

The LAVENDER tube contains which additive: Ethylenediamine tetraacetic acid or EDTA EDTA OR Ethylenediamine tetraacetic acid

answer

...

question

THE GREEN TUBE CONTAINS WHAT ADDITIVES: LITHIUM HEPARIN SODIUM HEPARIN AMMONIUM HEPARIN

answer

LITHIUM HEPARIN SODIUM HEPARIN AMMONIUM HEPARIN

question

THE YELLOW TUBES CONTAIN WHAT ADDITIVES: ACD AND SPS ACD AND SPS

answer

...

question

THE GRAY TUBE HAS WHAT ADDITIVE: POTASSIUM OXALATE SODIUM FLOURIDE

answer

...

question

What tubes contain GEL CLOT ACTIVATORS: TIGER TUBE (SPECKLED TOPPED TUBE)

answer

...

question

What tests are LIGHT BLUE tubes used for: PT: PROTHOMBINE TIME PTT: PARTIAL THROMBOPLASTINE TIME

answer

...

question

What tests are Green tubes used for: DRUG TESTING DNA ELECTROLYTES

answer

...

question

What tests are LAVENDER tubes used for: CBC:COMPLETE BLOOD COUNT ESR: ERTHROCYTE SEDIMENTATION RATE Hct: Hematocrit Hgb: Hemoglobin

answer

...

question

What tests are GRAY tubes used for: GTT: GLUCOSE TOLERANCE TEST FBS: FASTING BLOOD SUGAR BLOOD ALCOHOL 2 P.P: 2 HOURS POST PRANDIAL

answer

...

question

What tests are PINK TUBES tubes used for: BLOOD BANK

answer

...

question

What tests are TIGER (SPECKLED) tubes used for: HCG: HUMAN CHORIONIC GONADOTROPIN HIV: HUMAN IMMUNODEFICIENCY VIRUS PROFILES

answer

...

question

What tests are RED AND GOLD tubes used for: HCG: HUMAN CHORIONIC GONADOTROPIN ABO TYPE

answer

...

question

THE DEPARTMENTS OF COLORED TUBES IS AS FOLLOWS: HEMATOLOGY: LAVENDER COAGULATION: LIGHT BLUE TUBE CHEMISTRY: GOLD TUBE, RED TUBE, GREEN TUBE, TIGER TUBE SEROLOGY: GOLD OR RED TUBE BLOOD BANK: PINK (PRIMARY) LAVENDER (SECONDARY) MICROBIOLOGY: BLOOD CULTURE

answer

...

STUDY

A Level Biology AP Biology Bioinformatics Biology Genetic Material Of A Cell Genetics Microbiology

Week One Biochem Review – Flashcards 86 terms

Sam Arent

86 terms

Preview

Week One Biochem Review – Flashcards

question

Our genetic code is made up of DNA and are expressed in the phenotype as a __________.

answer

protein

question

What are the four characteristics of our DNA?

answer

Universal, unambiguous, redundant, non-overlapping & commaless

question

The genetic code consists of bases, these bases comprise _________.

answer

codons

question

The four bases are:

answer

A (adenine), T (thymine), C (cytosine), and G (guanine)

question

Since there are four bases, there are ____ possible codons

answer

question

DNA molecule is a double-helix- __________ _________.

answer

Rosalind Franklin

question

Meselson and Stahl experiment showed replication of DNA to be ________________.

answer

semiconservative

question

___________ unwinds the strand.

answer

helicase

question

_____________ ___________ sets up for the RNA primer

answer

RNA primase

question

_______ ___________ _________adds nucleotides to the 3’ end of the RNA primer and elongates the DNA strand

answer

DNA polymerase III

question

_________ __________ ___ removes the old RNA primer and replaces it with DNA

answer

DNA polymerase I

question

________ _________ catalyzes the formation of the phosphodiester bond linking the Okazaki fragments

answer

DNA ligase

question

___________ __________ action causes the newly forming leading strandto grow in the 5’-to-3’ direction

answer

DNA polymerase

question

________ uses DNA polymerases to repeatedly replicate DNA in the test tube.

answer

PCR (polymerase chain reaction)

question

RNA differs from DNA in 3 ways:

answer

1)it is single-stranded
2) its sugar molecule is ribose rather than deoxyribose
3) its fourth base is uracil rather than thymine

question

Messenger RNA =

answer

mRNA is the message or direction on how to make a protein

question

Transfer RNA =

answer

tRNA it matches up amino acids with the RNA message

question

Ribosomal RNA=

answer

rRNA used to bind the mRNA message

question

recognition sequence: one or two recognition sequences of 50 - 70bp form what?

answer

the TATA box

question

TATA box (rich in thymine & adinine): ___ base pairs upstream from the_____ ______ for transcription

answer

25; initiation site

question

_________ __________ _________ ___ needs transcription factors to initiate transcription

answer

Eukaryotic RNA polymerase II

question

The protein ______ binds to the TATA box

answer

TFIID

question

Finally _____ ______________ ____ binds to the site

answer

RNA polymerase II

question

_____ is transcribed from the DNA template after the ________ __ ____ are exposed by unwinding of the double helix.

answer

RNA;bases of DNA

question

RNA polymerase reads the DNA template strand from __ to __ and produces the RNA transcript from __ to __.

answer

3’ to 5’ ; 5' to 3'

question

Nucleotides are added at the __ end of the growing RNA

answer

question

One mRNA codon _____ indicates the starting point of translation, also codes for _____________.

answer

AUG; methionine

question

Three stop codons indicate the end of _________.

answer

translation - UAA, UAG and UGA

question

The other 60 codons code only for __________ ________ _________.

answer

particular amino acids.

question

_____ binds the correct amino acid; has an _______ complementary to the mRNA codon.

answer

tRNA ; anticodon

question

The _____________, a family of activating enzymes, attach specific amino acids to their appropriate tRNA’s, forming ________ tRNA’s.

answer

aminoacyl-tRNA synthetases; charged

question

The ribosome is composed of two units:
large subunit that consists of _____ different molecules of rRNA and ___ different ________ ________ .
small subunit of one ___ ________ and ___ different protein molecules

answer

3; 45; protein molecules;rRNA molecule; 33

question

An initiation complex consisting of an _______ _________ __________ _________ and a small ribosomal subunit bound to mRNA triggers the beginning of ____________.

answer

amino acid-charged tRNA; translation

question

On the large subunit of the ribosome there are ___ sites to which tRNA binds.

answer

four

question

T (transfer) site: where ___________.

answer

tRNA first lands

question

A (amino acid) site is where the tRNA anticodon binds to ___________.

answer

binds to mRNA codon

question

P (polypeptide) site is where the tRNA __________.

answer

adds its amino acid to the growing poly peptide chain

question

E (exit) site is where tRNA, without its ______ _______, resides before leaving the________ and going back to the cytosol to pick up another ________ _________.

answer

amino acid; ribosome; amino acid

question

Polypeptides grow from the __ terminus toward the __ terminus. The ribosome moves along the mRNA ___ codon at a time.

answer

N to C; one

question

The presence of a _____ ______ in the __ site of the ribosome causes translation to terminate

answer

stop codon; A

question

Signals contained in the amino acid sequences of proteins direct them to___________ ____________.

answer

cellular destinations.

question

Modifications of proteins after translation include:

answer

proteolysis, glycosylation, and phosphorylation.

question

Cells must regulate how they synthesize molecules to suit their:

answer

condition, environment, and needs

question

cells can control synthesis activity by
___________ or controlling the production
of _________.

answer

regulating; enzymes

question

cells can control synthesis activity by blocking __________ of the gene that codes for a protein.

answer

transcription

question

cells can control synthesis activity by _______ the ______ after it is made.

answer

hydrolyze; mRNA

question

cells can control synthesis activity by ________ __________ of mRNA at the ribosome.

answer

preventing translation

question

cells can control synthesis activity by __________ the protein after it was made

answer

hydrolyzing

question

Point mutations result from alterations in______ ________ ________ of DNA.

answer

single base pairs

question

What are some examples of point mutation?

answer

silent, missense, nonsense, or frame-shift

question

Chromosomal mutations involve _______ regions of a chromosome.

answer

large

question

What are some examples of chromosomal mutations>

answer

deletions, duplications, inversions, or translocations

question

Point mutations result from the _______ or _______ of one base for another in the DNA and as a result in the RNA

answer

addition or subtraction;

question

Some result in no change in amino acid because of the redundancy of the genetic code=

answer

silent or synonymous mutation

question

A ____________ mutation results in an amino acid change

answer

missense

question

____________ mutation results in no protein being made at all, they are disruptive.

answer

nonsense

question

____________ mutation results in no protein being made at all, they are disruptive.

answer

nonsense

question

A _________-__________ mutation, is when single base pairs may be inserted or deleted from DNA

answer

frame-shift

question

___________ remove part of the genetic material

answer

deletions

question

___________ mutations are homologous chromosomes brake at different positions and then reconnect to the wrong partners

answer

Duplications

question

_________ mutations are removal of a segment and its reinsertion into the same location but flipped.

answer

Inversion

question

___________ mutation is when a segment of DNA breaks off and is inserted into a different chromosome

answer

translocation

question

Spontaneous mutations occur because of instabilities in ______ or _____________.

answer

DNA or chromosomes

question

Induced mutations occur when an ________ __________ damages ____.

answer

outside agent; DNA

question

Some of these non-transcribed regions are ________, such as the telomeres; some regulate ______ ________; and some have no known use.

answer

structural; gene expression

question

____________ are 5-50bps are repeated side by side up to a million times.

answer

Satellites

question

________ are 12-100 bps long & are repeated several thousand times. Can be used as ______ _______ for identifying an individual because their numbers can vary

answer

Minisatellites; genetic markers

question

__________ are 1-5bps present in small clusters 10-50 copies. These have been used in sequencing the human genome

answer

microsatellites

question

___________ are repetitive sequences at the ends of chromosomes

answer

telomeres

question

Chromosome _________ occurs after each round of replication. This leads to ____ __________.

answer

shortening; cell death

question

The enzyme_____________ prevents the loss of telomeric ends

answer

telomerase

question

A ___ _______ is added to the 5’ end.

answer

G cap, GTP

question

A _______ __ _______ is added to the 3’ end

answer

poly A tail

question

_______ _____________ particle binds at the 5’ splice site and a second binds near the 3’ splice site

answer

Small ribonucleoprotein (snRNP) particle

question

____________ elements move about the genome

answer

Transposable

question

a _____________ consists of two transposable elements flanking another gene or genes. The entire transposon is copied and inserted as a unit.

answer

transposon

question

If the insertion takes place in a somatic cell, _________ may result

answer

cancer

question

If a transposon replicates not just itself but also an adjacent gene, the result may be _____ _____________.

answer

gene duplication

question

Transposons can result in:

answer

cancer cells, gene duplication, genetic variability, new genes

question

___________ _______ are instructions that specify the primary structures of a protein molecule (those that get transcribed into mRNA)

answer

structural genes

question

_________ are units of transcription; structural genes plus regulatory mechanisms.

answer

operons

question

__________ regions bind activator proteins that stimulate the transcription complex (promoter then binds RNA polymerase & transcription starts)

answer

enhancer regions

question

_________ -when attached to an operon, transcription shuts down

answer

repressor

question

__________ are negative regulatory regions; turn off transcription by binding to repressor

answer

silencers

question

___________ blocks RNA polymerase from binding & transcribing the structural genes, preventing synthesis of tryptophan pathway enzymes

answer

tryptophan;

question

When glucose levels are high:

answer

1. RNA polymerase cannot bind efficiently
2. Structural genes are not transcribed. This is adaptive when the cell does not require an alternative energy source

STUDY

A Level Biology Biology Genetics Put Into Action

Protein Synthesis Test Questions – Flashcards 6 terms

Daphne Armenta

6 terms

Preview

Protein Synthesis Test Questions – Flashcards

question

What is the role of RNA polymerase?

answer

question

Which describes a promoter?

answer

question

The diagram shows one step in the process of protein synthesis. http://media.education2020.com/evresources/3209-05-03/mc020-1.jpg Which step is shown?

answer

question

Where are proteins made?

answer

question

Which summary below correctly describes what occurs during transcription?

answer

question

Which occurs during transcription?

answer

STUDY

A Level Biology Cell Biology Microbiology Microbiology For Health Sciences

Chapter 5&6 – Flashcards 81 terms

Kaitlynn Baldwin

81 terms

Preview

Chapter 5&6 – Flashcards

question

Binary Fission

answer

An asexual process in bacterial and archaeal cells by which a cell divides to form two new cells while maintaining genetic constancy

question

Generation Time

answer

The time interval for a cell population to double in number

question

Incubation Period

answer

The time that elapses between the entry of a pathogen into the hose and the appearance of signs and symptoms

question

What are the phases of a population growth curve?

answer

Lag Phase- no cell divisions occur Log Phase- active stage of growth-primary metabolites are being synthesized Stationary Phase- reproductive and death rates equalize and plateau- environmental resistance is factors that limit population growth/secondary metabolites are produced these are chemicals not necessary for growth Decline Phase- nutrients become low and cells start dying off

question

Vegetative Cell

answer

Cells that actively metabolize and obtain nutrients

question

Endospore

answer

A dormant structure that persist during periods of unfavorable conditions

question

Dipocolinic Acid

answer

A chemical found in endospores that stabilizes its proteins and DNA

question

Sporulation

answer

Bacterial chromosome is replicated, One chromosome condenses, Asymmetric cell division partitions prespore from mother cell, Transverse septum forms and prespore is engulfed by mother cell, Cortex develops around the prespore followed by a piece of spore coat, Spore wall is complete; vegetative cell disintegrates, Free spore is released

question

Psychrophile

answer

A microbe that grows in cold temperatures

question

Mesophile

answer

A microbe that grows in moderate temperatures

question

Thermophile

answer

A microbe that grows in hot temperatures

question

Obligate Aerobe

answer

Requires O2 (Oxygen)

question

Obligate Anaerobe

answer

Cannot grow in the presence of O2 (Oxygen)

question

Facultative

answer

Can grow in the presence or absence of O2 (Oxygen)

question

Microaerophile

answer

Requires low concentrations of O2 (Oxygen)

question

Capnophile

answer

CO2 (Carbon Dioxide) loving organisms

question

Aerotolerant

answer

Anaerobe that can tolerate O2 (Oxygen) however does not derive any benefit from it

question

Halophile

answer

Lives in environments rich in salt

question

Hypotonic

answer

Solute concentration is lower than the cell. Water enters by osmosis. Cell becomes bigger

question

Isotonic

answer

Solute concentration is equal to that of the cell. Water is neither gained nor lost.

question

Hypertonic

answer

Solute concentration is higher than the cell. Water leaves by osmosis and the cell becomes smaller.

question

Synthetic Medium

answer

Chemically defined; contain highly purified organic and inorganic compounds.

question

Non-Synthetic Medium

answer

Also known as complex media contains at least one ingredient that is not chemically defined such as blood, serum, meat extract etc..

question

Carbon

answer

Serves as the backbone of organic molecules

question

Carbon Cycle

answer

Carbon enters the ecosystem by photosynthesis or chemoautotrophy and leaves by cellular respiration

question

Nitrogen

answer

Used for synthesizing proteins, DNA, RNA, and ATP

question

Nitrogen Cycle

answer

Nitrogen enters the ecosystem by nitrogen fixation and leaves by denitrification

question

Oxygen

answer

Major constituent of organic molecules, Required for aerobic cellular respiration

question

Hydrogen

answer

Major constituent of organic molecules, Involved in maintaining pH, Important for hydrogen bonding in macromolecules, Prime force in oxidation-reduction reactions of cellular respiration

question

Phosphorus

answer

Constituent of DNA, RNA, nucleotides, ATP, phospholipids, and coenzymes, PO43- is the primary inorganic source of the element

question

Sulfur

answer

Constituent of proteins, Cysteine and methionine are amino acids that contain sulfur

question

Microelements

answer

Compounds or substances needed in small amounts for proper functioning in the body.

question

Growth Factors

answer

Substances that cannot be synthesized and must be obtained as a nutrient such as temperature, oxygen, ph, hydrostatic and osmotic pressure

question

Fastidious Organism

answer

Require special growth factors

question

What are two major solidifying agents for media?

answer

Agar and gelatin

question

Which solidifying agent has the most disadvantages?

answer

Gelatin, it will not stay solid like agar it will melt

question

Synthetic Media

answer

Chemically defined; contains highly purified organic and inorganic compounds

question

Non-synthetic Media/Complex Media

answer

Contains at least one ingredient that is not chemically defined such as blood, serum, meat extract, infusions, milk, yeast extract, malt extract, soybean digests, and peptone

question

General Purpose Medium

answer

Designed to grow a broad spectrum of microorganisms such as TS broth, TSA, nutrient broth, and nutrient agar

question

Enriched Medium

answer

Enriched with blood, serum, hemoglobin, or special growth factors, Promotes the growth of fastidious organisms, Chocolate agar is an example

question

Selective Medium

answer

Contains a chemical that inhibits the growth of certain organisms, but promotes the growth of others, Lowenstein-jensen medium contains malachite green; this medium promotes the growth of mycobacterium while inhibiting other bacteria

question

Differential Medium

answer

Can grow several types of microorganisms, but can distinguish among them due to different appearances on the medium such as color of the colonies or color of the medium where the microorganisms are growing, Different types of gram-negative intestinal bacteria can be identified on chromacult agar due to the imparting of color to the colonies

question

Fermentation Medium

answer

Determines whether a microorganism can ferment a particular carbohydrate, Fermentation is an anaerobic process that often generates acids, If the carb is fermented acid is produced and can be detected by a ph indicator dye, Phenol red fermentation tubes turn yellow if the organism can ferment the sugar if it can’t it stays red

question

How can we isolate microorganisms in a mixed culture?

answer

By using the pour-plate method where the mixed culture is incubated on molten agar and after 24-48 hours the cells divide and form discrete colonies, or the streak-plate method where a series of streaks is made on the surface of nutrient agar of one area of the plate and dragged through all four sides after incubation each cell will grow to form a discrete colony on the plate

question

Turbidity

answer

Medium becomes cloudy as the number of microorganisms increase, this is measured with a spectrophotomer

question

Direct Count

answer

Involves counting the number of cells in a sample microscopically this is done with a cytometer

question

Viable Plate Count

answer

Determines the colony forming units of serially diluted samples using pour plate technique or spread plate technique

question

Most Probable Number

answer

A statistical estimation of the number of microorganisms by counting the number of tubes that demonstrate either turbidity or gas production

question

Filtration

answer

A known volume of liquid or air is passed through a filter that traps the microorganisms, A filter is placed on an agar medium and incubated the colonies are counted after the incubation period

question

What is are the differences between anabolism and catabolism?

answer

Anabolism is reactions that build up- buildup of small molecules, products are large molecules, mediated by enzymes, energy-requiring, Catabolism is reactions that break down- breakdown large molecules, products are small molecules, mediated by enzymes, energy releasing

question

What is a catalyst?

answer

A catalyst is a chemical agent that changes the rate of a reaction without being consumed in the reaction

question

What are the characteristics of enzymes?

answer

Enzymes are proteins that catalyze biochemical reactions, Enzymes are not consumed or permanently altered by the reaction, Enzymes are reusable, Enzymes exhibit specificity for their particular substrate, Enzymes are effective in low concentrations, Enzymes lower the energy of activation of a biochemical reaction, The names of enzymes typically end in the suffix -ase

question

Why are cofactors important for conjugated enzymes?

answer

Cofactors are organic or inorganic molecules that are required for the activity of a certain conjugated enzymes

question

Why is the active site important for enzyme function?

answer

An active site is the part of an enzyme that directly binds to a substrate and carries a reaction. It contains catalytic groups which are amino acids that promote formation and degradation of bonds. By forming and breaking these bonds, enzyme and substrate interaction promotes the formation of the transition state structure. Enzymes help a reaction by stabilizing the transition state intermediate. This is accomplished by lowering the energy barrier or activation energy- the energy that is required to promote the formation of transition state intermediate

question

What is an allosteric site? Why are they important for the regulation of metabolic pathways?

answer

An allosteric enzyme has a regulatory site as well as an active site. An inhibitory substance binds to the regulatory site and changes the shape of the enzyme distorting the active site. This prevents the substrate from binding to the active site inhibiting the enzymatic reaction.

question

Distinguish between competitive and non-competitive inhibitors.

answer

Competitive inhibitor is an inhibitor that binds to the avtive site it competes with the substrate for the active site but no product is made, Non-competitive inhibitor is an inhibitor that binds to another site where binding is irreversible

question

How do sulfa drugs work?

answer

Sulfa drugs act as competitive inhibitors of a bacterial enzyme. Bacteria need PABA in order to make metabolites leading to the making of folic acid which is necessary for DNA replication. Sulfa drugs out compete PABA. Since no product is made, no folic acid is made. The bacteria stop dividing because they are unable to perform DNA replication.

question

What factors can denature an enzyme?

answer

Denaturization occurs when there is an extreme change that causes the enzyme to become unstable and change its shape. The factors that can cause denaturization are temperature, pH, and osmotic pressure

question

Distinguish between exergonic and endergonic reactions

answer

Exergonic reaction is an energy releasing reaction- downhill to release energy to make ATP- catabolic, Endergonic reaction is an energy requiring reaction- uphill reaction- ATP needed for energy- anabolic

question

What are oxidation-reduction reactions?

answer

How cells transfer energy from one compound to another- always occurs in pairs- if one is oxidized a second is reduced- To remember oxidation and reduction; LEO the chemistry lion says GER! LEO: lose electrons oxidation, GER: gain electrons reduction

question

Explain the ATP cycle

answer

ATP is made by the phosphorylation of ADP: energy released from the oxidation of nutrient molecules provides the energy to make ATP

question

What is the role of coenzymes in cellular respiration?

answer

Coenzymes carries energy from the broken chemical bond of the substrate to the formation of the high energy bond of ATP Coenzymes act as mobile electron carriers, Coenzymes transport electrons to the electron transport chain where most of the ATP is made Most important coenzyme is NAD+

question

Summarize glycolysis

answer

Is a sugar splitting reaction that occurs in the cytosol of eukaryotic cell

question

Summarize the bridging step

answer

Step between glycolysis and citric acid cycle, Occurs in cytosol of eukaryotic cells, occurs twice for each molecule of glucose, pyruvic acid is converted into acetyl CoA, carbon dioxide is generated

question

Summarize the citric acid cycle

answer

Occurs twice for each molecule of glucose, occurs in the matrix of the mitochondrion or the eukaryotic cell and cytosol of the prokaryotic cell, carbon dioxide is generated, GTP is converted in ATP, the NADH and the FADH2 go to the electron transport chain

question

Summarize the electron transport chain

answer

A series of electron carriers bound to a membrane, occurs on the cristae of the mitochondrion of the eukaryotic cell and the mesosome of the prokaryotic cell, coenzymes drop off their electrons in the ETC, electrons are passed along a series of 9 carriers, oxygen is the terminal electron acceptor and is converted into water, as electrons are passed along the electron acceptors, energy is released to produce ATP

question

How many ATP molecules are made aerobically?

answer

38 ATPs for Prokaryotic 36 ATPs for Eukaryotic

question

Summarize how ATP is made by chemiosmosis

answer

Energy released in the electron transport chain is used to pump hydrogen across the membrane from the matrix into the intermembrane space.

question

What is anaerobic respiration? How many ATP molecules are made?

answer

Anaerobic respiration Is an energy releasing process that does not require oxygen, Anaerobic respiration is fermentation, only 2 ATPs are made

question

What is the function of fermentation?

answer

Fermentation pathway recycles coenzymes for ongoing glycolysis

question

Alcohol Fermentation

answer

Performed by fermentative yeasts, alcohol and carbon dioxide are produced

question

Homolactic Fermentation

answer

Produces lactic acid, performed by many bacteria, performed by our muscle tissue when oxygen levels fall

question

Heterolactic Fermentation

answer

Occurs in many bacteria, produces a comination of acids, also H2 and CO2

question

What is the methyl red test?

answer

Tests for acid products

question

What is the Voges-Proskauer test?

answer

Tests for neutral products

question

What is the difference between light-dependent and light-independent reaction?

answer

Light dependent needs light to react; light independent does not need light to react

question

Photoautotroph

answer

Needs co2 and light

question

Chemoautotroph

answer

Needs co2 and inorganic chemicals

question

Photoheterotroph

answer

Need organic molecules and light

question

Chemoheterotroph

answer

Need organic molecules and organic chemicals

question

What is the difference between a saprobe and a parasite?

answer

Saprobes feed on dead organic matter Parasites feed on living organic matter

STUDY

A Level Biology Biology

Microbiology Lab Test 1 – Flashcards 104 terms

Ruth Blanco

104 terms

Preview

Microbiology Lab Test 1 – Flashcards

question

Exercise 1.1
Name the parts of a microscope and state the function of each.

answer

Base - Support for microscope
Substage light - Illumination source located on base of microscope which shines light up through the condenser to the slide and object being viewed
Stage - platform that supports slides for viewing
Mechanical stage and control knobs - Apparatus which holds slides in place and which is used to adjust the (X and Y) position of the slide on the stage
Condenser - Substage lens that focuses the light on the specimen so that each of its points are evenly illuminated
Condenser knob - used to adjust the condenser up and down
Iris diaphragm lever - Opens and closes the condenser, thus regulating the amount of light shining through the condenser onto the object. Helps control contrast on the specimen
Coarse adjustment knob - Used with lower power objective lens to bring an object roughly in focus
Fine adjustment knob - used for fine focusing of all objective lenses
Head - Supports the ocular and objective lenses
Arm - Portion of microscope connecting the head and base
Ocular or eyepiece - Lens closest to the eye which magnifies the image produced by the objective lens
Rotating nosepiece (turret)- Structure on the head that holds all the objective lenses and which may be rotated to change from one lens to another
Objective lenses - lens closest to the specimen which magnifies the specimen
Scanning power - Generally about 4x magnification
Low power - generally about 10x magnification
High power - generally about 40x magnification
Oil immersion lens - Generally about 100x magnification and utilizes oil so that a more highly magnified and sharper image may be obtained
Rheostat - Used to vary the intensity of light

question

Exercise 1.2
What are the total magnifications obtained with each objective lens?

answer

1,000, 100, 450

question

Exercise 1.3
What is the resolution of this type of microscope?

answer

0.2um

question

Exercise 1.4
Why is blue light used when possible?

answer

Because blue light has the shortest wavelength of all visible light and resolution is inversely proportional to wavelength of light

question

Exercise 1.5
What is the proper method to carry a microscope?

answer

With two hands. One hand holds the base and the other is on the arm of the microscope

question

Exercise 1.6
What has to be used with every 100x objective lens? Why?

answer

Immersion oil because it increases the numerical aperture of the objective lens and prevents wide angles of light from being refracted away from the lens

question

Exercise 1.7
This scope is parfocal. What does that mean?

answer

Once focused with a low power objective, the image remains always in focus for the other objective lenses, or very nearly in focus. This makes finding your specimen at high power much easier

question

Exercise 1.8
Which objective lens has the smallest working distance?

answer

100x

question

Exercise 1.9
What are the three basic bacterial shapes?

answer

Bacilli (rod), cocci (spherical), spiral (helical)

question

Exercise 1.10
What is always done to a microscope after using the 100x objective lens before it is put away in the cabinet?

answer

Clean off the oil from the lens

question

Exercise 2.1
Will the media prepared from this powder be a liquid or solid media?
How do you know (besides looking at the name of the medium)?

answer

Solid. Look at the list of ingredients and look for the solidifying agent, agar

question

Exercise 2.2
How should this medium be sterilized prior to its use?

answer

Autoclave at 15psi for 15 min, at 121 degrees C

question

Exercise 2.3
To make up 500 ml of this media, how much of the following would you needa)water
b)Dehydrated media

answer

a)500 ml
b)20 g

question

Exercise 2.4
What percentage of casein will be in the final medium?

answer

1.5% casein (15 grams in 1000 ml is like 1.5 in 100 ml, which would be 1.5%)

question

Exercise 3.1
Be sure you know the basic aseptic microbiological transfer techniques you learned in Exercise 3

answer

See Exercise 3 for specific details; review the proper techniques and sequences for transferring organisms from one type of media to another

question

Exercise 3.2
If you wanted to isolate single colonies from a mixed culture, what type of culture would you use (e.g. streak plate, agar slant, broth)?

answer

Streak plate method (isolated colonies on an agar plate)

question

Exercise 3.3
If you wanted to keep a pure culture of bacterium for a long time (weeks or a couple of months), what type of culture would you use (streak plate, agar slant, or broth)?

answer

An agar slant

question

Exercise 4.1.1
What reagents did you use (and in what order) for each of the following stainsa)Gram stain (Lab 4)
b)Schaffer-Fulton Endospore stain (Lab 8)
c)Capsule stain (Lab 11)

answer

a) Crystal Violet, Iodine, Ethanol, Safranin
b)Malachite Green, Safranin
c)Capsule stain:
1)Mix equal amounts of India ink and water on glass slide, then add a loop of culture. Gently stir and spread mixture.
2)Allow smear to dry without heat fixation
3)Counterstain with methylene blue for 3 minutes
4)Rinse the slide very carefully and dry
5)Oil immersion. Blue cells w/ clear capsules on a black background

question

Exercise 4.1.2
What is the function of each of the reagents for these stains

answer

a)Gram Stain
Crystal violet - Primary stain
Iodine - Mordant (fixes stain)
Ethanol - Decolorizer
Safranin - Counterstain
b)Schaffer-Fulton Endospore Stain
Malachite Green - Primary stain
Safranin - Counterstain
c)Capsule stain
India ink - stain Methylene blue - counterstain

question

Exercise 4.1.3
What procedure is used to apply and fix a bacterial smear for staining?

answer

Bacterial smears are prepared by placing a drop of broth culture on a clean microscope slide and spreading it in a circular motion. The smear is allowed to air dry and fixed by lightly passing it through the flame. If a smear is made from bacterial growth on an agar surface, a small drop of water is first placed on the slide and a very small amount of bacterial growth is emulsified in the drop to make a lightly turbid smear. It is also dried and fixed by flaming.

question

Exercise 4.1.4
What about the bacterial cell is responsible for the characteristic response of a cell wall to the Gram stain?

answer

Gram Stain - The Gram stain reaction is dependent upon the nature of the cell wall of the bacterium. The Gram positive bacteria have a thick layer of peptidoglycan, which is able to hold the crystal violet-iodine complex within the cell wall when alcohol is applied. The Gram negative cell wall has only a thin layer of peptidoglycan with a lipid membrane around it. When the alcohol is applied it is not thick enough to hold the crystal violet-iodine complex.

question

Exercise 4.2.1
Describe the arrangement of flagella on the bacterium shown in the figure below:
[image]

answer

Peritrichous - Many randomly all over (non-polar)

question

Exercise 4.2.2
Can you name and describe the other types of flagellar arrangements?

answer

Flagella Arrangements:
a)Monotrichous - Single flagella at one end (polar)
b)Lophotrichous - Many from one end (polar)
c)Amphitrichous - One or more at each end (bi-polar)
d) Peritrichous - Many randomly all over (non-polar)

question

Exercise 4.3.1
What does the clear zone represent in this India ink preparation[image]

answer

Capsule

question

Exercise 4.3.2
[image]
What is the function?

answer

Protection against phagocytosis (inside the body) and dehydration (outside the body)

question

Exercise 4.3.3
[image]
What two pneumonia-causing bacteria are noted for their large capsules?

answer

Streptococcus pneumonia and Klebsiella pneumoniae

question

Exercise 4.3.4
[image]
Which one of the two would this one be? support your answer

answer

This one would be Klebsiella pneumoniae because Klebsiella is a bacillus and Streptococcus is a coccus

question

Exercise 5.1.1
[image]
What fungus produced this special type of spore a)What is the function of fungal spores b)How does this function differ from the primary function of bacterial endospores?

answer

Histoplasma capsulatum
a)Spores of fungi are primarily used by these microbes for reproduction. One mold can produce millions of spores, each of which can produce a new fungus colony. The spores also serve for dispersal and survival in dry situations.
b)The function of fungal spores contrasts with that of bacterial endospores whose essential function is for survival in unfavorable environments. Bacterial endospores are not used for reproduction/increases in number. One cell can only produce one endospore that germinate into one bacterial cell

question

Exercise 5.1.2
[image]
Name the disease cause by this fungus

answer

Histoplasmosis

question

Exercise 5.1.3
[image]
At what temperature would the fungus have to grow to produce these spores?

answer

25 degrees Celsius

question

Exercise 5.1.4
[image]
What is the phase of growth called?

answer

Mold

question

Exercise 5.1.5
[image]
What is the specific name given to this spore type?

answer

Tuberculated chlamydospore

question

Exercise 5.1.6
[image]
In what part of the country is this fungus found?

answer

U.S.A. (Eastern) Ohio and Mississippi River Valleys

question

Exercise 5.1.7
[image]
How does one acquire this fungus infection?

answer

Inhalation of the infectious tuberculated chlamydospores

question

Exercise 5.2.1
Look at the photo provided with this station ("Histoplasma capsulatum" page on fb) and notice the large, encapsulated yeast cells.
Name the following:
a)Disease
b)Fungus
c)Phase of growth

answer

a)Cryptococcosis
b)Cryptococcus neoformans
c)Yeast phase

question

Exercise 5.3
These are opportunistic yeast cells
[image]
1)What genus and species would be seen in this slide2)What disease could these cells cause3)How do yeast reproduce?

answer

1)Candida albicans
2)Thrush, vaginitis, cutaneous candidiasis
3)Budding from mother cell

question

Exercise 5.4.1
What type of organism is this? What is the name of this organism[image]

answer

This is a fungus known as Aspergillus

question

Exercise 5.4.2
Is this organism a human pathogen[image]

answer

Aspergillus is an opportunistic pathogen of humans causing primarily respiratory tract infections (Aspergillosis)

question

Exercise 5.4.3
What is the name of the toxin produced by this organism[image]

answer

Aflatoxin

question

Exercise 5.4.4
What are some of the complications of this toxin[image]

answer

Can cause acute necrosis and cirrhosis of the liver leading to liver cancer

question

Exercise 6.1.1
This is a tube of semisolid motility medium:
[image]
a)If there are two tubes displayed, which of the two tubes contains the motile bacteriab)If there is only one tube displayed, are the bacteria in this tube motile? How can you tell?

answer

a) The motile bacteria would be in the tube where there is turbidity extending from the center inoculation stab. The one with the bacteria growing only down the center in the inoculation stab is the non-motile bacteria
b) No, one can tell because turbidity has not spread from the center stab line. Non-motile bacteria grow only along the stab and do not "swim" out from it to make the surrounding media turbid.

question

Exercise 6.1.2
[image]
What other techniques can be used to determine bacterial motility?

answer

Flagella stain, hanging drop slide

question

Exercise 6.1.3
[image]
By what means are most bacteria motile?

answer

Flagella

question

Exercise 6.1.4
[image]
What organelles are used by spirochetes for motility?

answer

Axial filaments

question

Exercise 6.2.1
What is this slide called[image]

answer

Concave or concavity slide

question

Exercise 6.2.2
What is it used for[image]

answer

Motility observations using hanging drop preparations

question

Exercise 6.2.3
What other techniques are used to demonstrate the same thing[image]

answer

Flagella stain, semisolid motility medium

question

Exercise 7.1.1
Does ordinary hand washing remove all bacteria from the skin? Does a surgical scrub?

answer

Ordinary hand washing does not remove all bacteria from the skin neither does a surgical scrub.

question

Exercise 7.1.2
Explain why hand washing is still done to prevent the transmission of disease

answer

To remove transient microbes (bacteria, viruses, fungi, etc.) that could be pathogenic and to reduce the contamination level of the skin

question

Exercise 7.2.1
If surgical scrubbing does not remove all the microbes, why do a surgical scrub?

answer

See experiment 7

question

Exercise 7.2.2
What type of medium is blood agar?

answer

Enriched medium. It is also differential media because it allows one to determine the hemolytic patterns

question

Exercise 7.2.3
Acquiring an infection from the rim of a drinking glass would be an example of transmission via a/an...

answer

Fomite

question

Exercise 8.1.1
What stain(s)/ staining procedure was used on this slide[image]

answer

Schaffer-Fulton Endospore stain

question

Exercise 8.1.2
[image]
What genus of bacterium are these? What disease does this genus cause?

answer

Bacillus, anthrax (or Clostridium, gas gangrene, tetanus, botulism, pseudomembranous colitis)

question

Exercise 8.1.3
What is the function of the green structures[image]

answer

The green structures are the bacterial endospores, used as a survival strategy during harsh conditions/lack of nutrients/lack of water

question

Exercise 8.1.4
What special procedure has to be followed to stain the spores[image]

answer

Heating for 4 minutes in the presence of Malachite green stain

question

Exercise 8.1.5
What dye in the stain was taken up by the following[image]
a)Vegetative cells
b)Endospore

answer

Dye components take up by different parts:
a)Safranin
b)Malachite green

question

Exercise 8.2.1
These bacteria (reddish bacilli) and tissue were taken from a diseased cow. Upon growth in the laboratory, endospores were formed
[image]
Name the disease that most likely killed this cow.

answer

Anthrax

question

Exercise 8.2.2
These bacteria (reddish bacilli) and tissue were taken from a diseased cow. Upon growth in the laboratory, endospores were formed
[image]
What bacteria caused this disease?

answer

Bacillus anthracis

question

Exercise 8.3.1
[image]
Name this apparatus

answer

Anaerobic jar (chamber)

question

Exercise 8.3.2
[image]
What is its function?

answer

To provide anaerobic conditions for bacteria that require this type of atmospheric environment

question

Exercise 8.3.3
What bacterial genus we studied this semester is grown in this type of apparatus[image]

answer

Clostridium

question

Exercise 8.3.4
What diseases are caused by these bacteria (Clostridium)?

answer

Gas gangrene, tetanus, botulism

question

Exercise 8.3.5
What other techniques are used to provide anaerobic conditions?

answer

Cooked meat medium, thioglycollate medium, anaerobic incubator

question

Exercise 8.3.6
Can a candle jar be used? Why or why not? What is it used for?

answer

No, a candle jar cannot be used because the candle goes out before all the oxygen is burned up. Candle jars are used to provide an atmosphere with increased carbon dioxide for those bacteria such as Neisseria that grow better with it.

question

Exercise 9.1.1
Review the Kinyoun Acid Fast Stain procedure

answer

Kinyoun Acid Fast Stain procedure:
a)Flood air-dryed smear with Kinyoun Carbol Fuchsin for 5 min.
b)Rinse with water
c)Decolorize with Acidified alcohol
d)Rinse with water
e)Counterstain with Brilliant Green (or methylene blue) for 30 seconds
f)Rinse with water, blot dry, observe under oil-immersion

question

Exercise 9.1.2
What color do Acid fast cells appear after this staining procedure?

answer

Acid fast cells (mycobacteria) should appear red

question

Exercise 9.1.3
What is the name of the "waxy" lipid in the cell walls of Mycobacteria?

answer

The walls of mycobacteria contain Mycolic Acid

question

Exercise 9.1.4
Name at least two diseases caused by Mycobacterium

answer

Diseases:
a)Tuberculosis caused by Mycobacterium tuberculosis
b)Leprosy (Hansen's disease) caused by Mycobacterium leprae

question

Exercise 10.1.1
Did regrigeration kill the bacteria in the experiment? How was this shown?

answer

No. When placed in the incubator after refrigeration the bacteria grew into colonies demonstrating that they were not killed but were merely inhibited from growing.

question

Exercise 10.1.2
What term is used for a procedure that inhibits the growth of bacteria rather than killing them?

answer

The term bacteriostatic is used for inhibition of bacterial growth (microbiostatic would be used for any microbe, fungistatic for fungi, etc.)

question

Exercise 10.1.3
Which of the two bacteria in this experiment was not killed by heating in the steam bath? Why?

answer

The Bacillus culture was able to grow after being exposed to 70C+ because it forms endospores that are resistant to temperatures this high. Vegetative cells cannot survive temperature this high

question

Exercise 10.1.4
What term is used for a procedure that kills or destroys bacteria?

answer

The term bacteriocidal is used for procedures that destroy or kill bacteria (microbiocidal for microbes in general, virucidal for viruses, etc.)

question

Exercise 10.1.5
Which of the bacteria were killed by autoclaving?

answer

Both bacteria were killed by autoclaving. Autoclaving destroys all microorganisms

question

Exercise 10.1.6
What is the normal time and temperature (and pressure if applicable) of the following methods of microbial controla)Autoclave
b)Dry oven
c)Boiling

answer

a)Autoclave - 121C, 15 mins, 15psi
b)Dry oven - 160-170C, 120-180 mins
c)Boiling - 100C, 15-20 mins

question

Exercise 10.2.1
This is a photo of an antibiotic disk susceptibility test:
[image]
What is the formal name of this test?

answer

Kirby Bauer Disk susceptibility Test

question

Exercise 10.2.2
This is a photo of an antibiotic disk susceptibility test
[image]
How would you determine if the bacteria cultured on these plates were susceptible to the antibiotics contained in the paper disks?

answer

Check the ones with the zones. To be accurate you would need a table of values to determine susceptible, intermediate, or resistant

question

Exercise 10.2.3
This is a photo of an antibiotic disk susceptibility test
[image]
Why are some zones larger than others? Does a larger zone necessarily mean that the antibiotic is more effective?

answer

Because the size of the zone is inversely proportional to the size of the antibiotic molecule. Smaller molecules will diffuse faster and create larger zones of inhibition. Remember: One cannot compare the effectiveness of different antibiotics by their zones of inhibition in this test

question

General Concepts 1
General Concepts from Selected Laboratory Exercises
How were the following features of bacteria demonstrated in the laboratoryBacterial Capsules

answer

Exercise 11:
Learned Gin's method of staining which consisted of India ink and Methylene blue stain

question

General Concepts 2
General Concepts from Selected Laboratory Exercises
How were the following features of bacteria demonstrated in the laboratoryBacterial motility

answer

Chapter 6:
Learned how to do a hanging drop slide using a concavity slide

question

General Concepts 3
General Concepts from Selected Laboratory Exercises
How were the following features of bacteria demonstrated in the laboratoryResistance of bacteria to antibiotics

answer

question

General Concepts 4
General Concepts from Selected Laboratory Exercises
How were the following features of bacteria demonstrated in the laboratoryDestruction of bacteria by autoclave and oven

answer

Chapter 10:

question

General Concepts 5
General Concepts from Selected Laboratory Exercises
How were the following features of bacteria demonstrated in the laboratoryEffectiveness of hand washing on hand disinfection

answer

Chapter 7 experiment 3:

question

General Concepts 6
General Concepts from Selected Laboratory Exercises
How were the following features of bacteria demonstrated in the laboratorySafety of cafeteria eating utensils

answer

Chapter 7 experiment 2:

question

General Concepts 7
General Concepts from Selected Laboratory Exercises
How were the following features of bacteria demonstrated in the laboratoryBacterial spores

answer

question

Exercise 1.1.1
Referring to a microscope, state the function of the base

answer

Support for microscope

question

Exercise 1.1.2
Referring to a microscope, state the function of the substage light

answer

Illumination source located on base of microscope which shines light up through the condenser to the slide and object being viewed

question

Exercise 1.1.3
Referring to a microscope, state the function of the stage

answer

Platform that supports the slide for viewing

question

Exercise 1.1.4
Referring to a microscope, state the function of the mechanical stage and control knobs

answer

Apparatus which holds slides in place and which is used to adjust the (X and Y) position of the slide on the stage

question

Exercise 1.1.5
Referring to a microscope, state the function of the condenser

answer

Substage lens that focuses the light on the specimen so that each of its points are evenly illuminated

question

Exercise 1.1.6
Referring to a microscope, state the function of the condenser knob

answer

used to adjust the condenser up and down

question

Exercise 1.1.7
Referring to a microscope, state the function of the iris diaphragm lever

answer

Opens and closes the condenser, thus regulating the amount of light shining through the condenser onto the object. Helps control contrast on the specimen

question

Exercise 1.1.8
Referring to a microscope, state the function of the coarse adjustment knob

answer

Used with lower power objective lens to bring an object roughly in focus

question

Exercise 1.1.9
Referring to a microscope, state the function of the fine adjustment knob

answer

used for fine focusing of all objective lenses

question

Exercise 1.1.10
Referring to a microscope, state the function of the head

answer

Supports the ocular and objective lenses

question

Exercise 1.1.11
Referring to a microscope, state the function of the arm

answer

portion of microscope connecting the head and base

question

Exercise 1.1.12
Referring to a microscope, state the function of the ocular or eyepiece

answer

Lens closest to the eye which magnifies the image produced by the objective lens

question

Exercise 1.1.13
Referring to a microscope, state the function of the rotating nosepiece (turret)

answer

Structure on the head that holds all the objective lenses and which may be rotated to change from one lens to the other

question

Exercise 1.1.14
Referring to a microscope, state the function of the objective lens

answer

lens closest to the specimen which magnifies the specimen

question

Exercise 1.1.15
Referring to a microscope, state the function of the scanning power

answer

Generally about 4x magnification

question

Exercise 1.1.16
Referring to a microscope, state the function of the low power

answer

Generally about 10x magnification

question

Exercise 1.1.17
Referring to a microscope, state the function of the high power

answer

Generally about 40x magnification

question

Exercise 1.1.18
Referring to a microscope, state the function of the oil immersion lens

answer

Generally about 100x magnification and utilizes oil so that a more highly magnified and sharper image may be obtained

question

Exercise 1.1.19
Referring to a microscope, state the function of the rheostat

answer

used to vary the intensity of light

STUDY

A Level Biology Biochemistry Biology Organic Chemistry 1

Biochemistry and cell organelles – Flashcards 83 terms

Tiffany Hanchett

83 terms

Preview

Biochemistry and cell organelles – Flashcards

question

eukaryotic cell

answer

has a nucleus, membrane bond organelles, plants, animals, fungi, protists

question

prokaryotic cell

answer

A type of cell lacking a membrane-enclosed nucleus and membrane-enclosed organelles; found only in the domains Bacteria and Archaea.

question

ribosomes

answer

non membrane bounded organelles responsible for protein synthesis

question

Smooth Endoplasmic Reticulum

answer

no ribosomes are found on surface; contains collection of enzymes that perform special tasks that include the synthesis of membrane lipids and detoxification; the liver contains a lot of smooth er

question

Rough Endoplasmic Reticulum

answer

ER that has ribosomes embedded in its walls. It operates by threading polypeptides into the lumen, letting the protein fold without the influence of the cytosol. Usually produces proteins that will be secreted

question

Golgi Apparatus

answer

An organelle in eukaryotic cells consisting of stacks of flat membranous sacs that modify, store, and route products of the endoplasmic reticulum.

question

Lysosome

answer

membrane-bound sac containing digestive enzymes that can break down proteins, nucleic acids, and polysaccharides

question

vacuole

answer

storage structures for food, water, minerals, waste

question

mitochondria

answer

Powerhouse of the cell, organelle that is the site of ATP (energy) production

question

chloroplast

answer

organelle found in cells of plants and some other organisms that captures the energy from sunlight and converts it into chemical energy

question

cytosol

answer

the aqueous part of the cytoplasm within which various particles and organelles are suspended

question

cytoplasm

answer

region of a cell between the nucleus and the plasma membrane

question

cell membrane

answer

thin, flexible barrier around a cell; regulates what enters and leaves the cell

question

cell wall

answer

a rigid layer of nonliving material that surrounds the cells of plants and some other organisms

question

peroxisome

answer

A microbody containing enzymes that transfer hydrogen from various substrates to oxygen, producing and then degrading hydrogen peroxide.

question

cytoskeleton

answer

a microscopic network of actin filaments and microtubules in the cytoplasm of many living cells that gives the cell shape and coherence

question

monosaccharide

answer

The simplest carbohydrate, active alone or serving as a monomer for disaccharides and polysaccharides. Also known as simple sugars, the molecular formulas of monosaccharides are generally some multiple of CH20.

question

disaccharide

answer

A molecule composed of two monosaccharides. Common disaccharides include maltose, sucrose, and lactose.

question

carbohydrates

answer

substances in food that consist of a single sugar molecule or of multiples of them in various forms. They provide the body with energy.

question

starch

answer

a complex carbohydrate found chiefly in seeds, fruits, tubers, roots and stem pith of plants, notably in corn, potatoes, wheat, and rice

question

glycogen

answer

An extensively branched glucose storage polysaccharide found in the liver and muscle of animals; the animal equivalent of starch

question

cellulose

answer

polysaccharide consisting of glucose monomers that reinforces plant-cell walls

question

chitin

answer

in the cell wall of hyphae, a polysaccharide that also makes up the exoskeleton of insects, crustaceans, and other anthropods

question

dehydration synthesis

answer

a chemical reaction in which large molecules are formed by removing water from smaller molecules and joining them together

question

hydrolysis

answer

a chemical process in which a compound is broken down and changed into other compounds by taking up the elements of water.

question

monomer

answer

a simple compound whose molecules can join together to form polymers

question

polymer

answer

large molecule formed when many smaller molecules bond together

question

glucose

answer

a monosaccharide sugar that has several forms

question

galactose

answer

A monosaccharide (or simple sugar), found in dairy products.

question

lactose

answer

a sugar comprising one glucose molecule linked to a galactose molecule

question

enzyme

answer

any of several complex proteins that are produced by cells and act as catalysts in specific biochemical reactions

question

lactase

answer

enzyme that catalyzes breakdown of lactose into glucose and galactose

question

amylase

answer

enzyme in saliva that breaks the chemical bonds in starches

question

peristalsis

answer

the process of wave-like muscle contractions of the alimentary tract that moves food along

question

bolus

answer

A term used to describe food after it has been chewed and mixed with saliva

question

jejunum

answer

second part of the small intestine

question

duodenum

answer

the part of the small intestine between the stomach and the jejunum

question

ileum

answer

the part of the small intestine between the jejunum and the cecum

question

cecum

answer

The first portion of the large intestine

question

appendix

answer

a vestigial process that extends from the lower end of the cecum and that resembles a small pouch

question

phospholipid

answer

A lipid made up of glycerol joined to two fatty acids and a phosphate group, giving the molecule a nonpolar hydrophobic tail and a polar hydrophilic head; form bilayers that function as biological membranes.

question

steroid

answer

A type of lipid whose carbon skeleton is in the form of four fused rings with various chemical groups attached; examples are cholesterol, testosterone, and estrogen.

question

saturated fatty acid

answer

A fatty acid in which all carbons in the hydrocarbon tail are connected by single bonds, thus maximizing the number of hydrogen atoms that can attach to the carbon skeleton., solid at room temperature, animal derived, all carbons have single bonds to hydrogens

question

unsaturated fatty acid

answer

A fatty acid possessing one or more double bonds between the carbons in the hydrocarbon tail. Such bonding reduces the number of hydrogen atoms attached to the carbon skeleton., liquid at room temperature, plant derived, not all carbons have bonds to hydrogen, one or more double covalent bonds

question

polyunsaturated fatty acid

answer

an unsaturated fatty acid whose carbon chain has more than one double or triple valence bond per molecule; found chiefly in fish and corn and soybean oil and safflower oil

question

amino acids

answer

building blocks of proteins

question

proteins

answer

Molecules made by connecting amino acids via peptide bonds. Proteins are synthesized (translated) by ribosomes, and function as enzymes, carriers, structrual fibers, cell surface receptors, channels, porters, hormones, etc., made up of amino acids

question

nucelic acids

answer

DNA: 100 million to 1 billion nucleotides long, contains genetic code, cell division, sexual reproduction, protein synthesis; RNA-3 types, transfer RNA, messenger RNA, ribosomal RNA, 70 to 10,000 nucleotides long, involved in protein synthesis coded for by DNA

question

nucleotides

answer

Basic units of DNA molecule, composed of a sugar, a phosphate, and one of 4 DNA bases

question

nitrogen bases

answer

adenine cytosine guanine thymine uracil

question

ATP

answer

a nucleotide derived from adenosine that occurs in muscle tissue

question

cellular respiration

answer

process that releases energy by breaking down glucose and other food molecules in the presence of oxygen. Takes place in the mitochondria

question

fermentation

answer

cellular process of making ATP without oxygen

question

covalent bonds

answer

form when electrons are shared between atoms

question

ionic bonds

answer

formed when one or more electrons are transferred from one atom to another

question

hydrogen bonds

answer

very weak bonds; occurs when a hydrogen atom in one molecule is attracted to the electrostatic atom in another molecule

question

van der waals interactions

answer

Attractions between molecules that are close together as a result of positive and negative charges, collectively these interactions can be strong; example: gecko's toe hairs and a wall surface

question

isomer

answer

compounds with the same simple formula but different three-dimensional structures resulting in different physical and chemical properties

question

isotopes

answer

atoms of the same element that have different numbers of neutrons

question

catabolic reaction

answer

breakdown of more complex substances into simpler ones with release of energy

question

anabolic reaction

answer

synthesis of more complex substances from simpler ones

question

anion

answer

a negatively charged ion

question

cation

answer

a positively charged ion

question

activation energy

answer

the energy that an atomic system must acquire before a process (such as an emission or reaction) can occur

question

catalyst

answer

(chemistry) a substance that initiates or accelerates a chemical reaction without itself being affected

question

coenzyme

answer

a small molecule (not a protein but sometimes a vitamin) essential for the activity of some enzymes

question

allosteric site

answer

A site on an enzyme other than the active site, to which a specific substance binds, thereby changing the shape and activity of the enzyme.

question

active site

answer

the site on an enzyme that attaches to a substrate

question

allosteric inhibitor

answer

Molecule binds to an enzyme somewhere other than active site and inhibits.

question

noncompetitive inhibitor

answer

A substance that reduces the activity of an enzyme by binding to a location remote from the active site, changing its conformation so that it no longer binds to the substrate.

question

cofactor

answer

Any nonprotein molecule or ion that is required for the proper functioning of an enzyme. Cofactors can be permanently bound to the active site or may bind loosely with the substrate during catalysis.

question

allosteric activator

answer

binds to a regulatory site (not active site, often located where subunits join), which stabilizes the shape that has functional active sites

question

first law of thermodynamics

answer

The principle of conservation of energy. Energy can be transferred and transformed, but it cannot be created or destroyed.

question

high specific heat

answer

Take more energy to change the temperature, Third unique property of water., amount of heat needed to raise the temp of 1g of substance 1 degree C, takes a while for it to reach boiling point so that it stays cool enough to organisms to benefit from it.

question

cohesion

answer

attraction between molecules of the same substance

question

adhesion

answer

an attraction between molecules of different substances

question

capillary action

answer

the combined force of attraction among water molecules and with the molecules of surrounding materials, one of the forces that draws water out of the roots of a plant and up into its stems and leaves.

question

surface tension

answer

A measure of how difficult it is to stretch or break the surface of a liquid. Water has a high surface tension because of the hydrogen bonding of surface molecules.

question

aquaporins

answer

a transport protein in the plasma membrane of a plant or animal cell that specifically facilitates the diffusion of water across the membrane

question

collagen

answer

Structural protein found in the skin and connective tissue

question

hemoglobin

answer

iron-containing protein in red blood cells that carries oxygen for delivery to cells

question

antibodies

answer

proteins that recognize and bind to antigens

question

antigens

answer

foreign substances that trigger the attack of antibodies in the immune response.

STUDY

A Level Biology Biology Molecular Biology Plant And Animal Cells

Biochemistry DNA and RNA – Flashcards 42 terms

Rebecca Mallory

42 terms

Preview

Biochemistry DNA and RNA – Flashcards

question

What are the components of nucleotides?

answer

3 components: 1. Nitrogenous base 2. pentose sugar (5 carbon atoms) 3. Phosphate group

question

What are the differences between purine and pyrimidine structures?

answer

Purine: Adenine (A), Guanine (G)> 2 ring bases Pyrimidine: Cytosine (C), Thymine (T), Uracil (U)> 1 ring bases CUT PY and PUR As AG

question

Describe the hydorgen bonds between A, T, C, G

answer

A double hydrogen bonds T G triple hydrogen bonds C

question

Define phosphodiester bonds

answer

Nucleotide unitls aer connected via 3' carbon and 5' carbon atoms (3' to 5' and 5' to 3')=phospodiester bonds

question

What are the differences between DNA and RNA with regards to replication?

answer

DNA: replicates itself once before cell division RNA: made continuously

question

What is helicase?

answer

Enzyme that separates DNA molecule to form a replication bubble. Replication fork: Y-shaped region

question

Define ORC binding to DNA

answer

Origin recognition complex and has 6 proteins. Requires presence of single stranded binding protein (SSBP) or Minichromosomal maintenance proteins (MCMs) to coat DNA and permit ORC binding.

question

How are MCMs removed in DNA replication?

answer

They are destroyed by ubiquitinylation.

question

Classes of RNA molecules

answer

3 classes: 1. rRNA: ribosomal RNA; were proteins are made 2. tRNA: transfer RNA; hold amino acids 3. mRNA: messenger RNA; DNA template

question

Ribosomal RNA (rRNA)

answer

-Interact with each other and with proteins to form ribosomes -Ribosomes provide basic machinery where protein synthesis takes place -Synthesized on single strand RNA transcript -60s subunit: 28s, 5.8s and 5s: associate to form larger subunit -40s subunit: 18s rRNA associates with proteins -80s: large and small subunits combine to form ribosome

question

Transfer RNA (tRNA)

answer

1. 65-110 nucleotides long 2. Functions: a) carries amino acids b) recognize mRNA nucleotide sequence c) translate sequence into amino acid sequence of proteins 3. Cloverleaf structure with 4 loops: a) D loop: contains methyicted cytosine and dihydrouridine b) Anticodon loop: responsible for recognition of the complementary codon of an mRNA c) T psi C loop: contains pseudoruidine d) Acceptor stem: i) last 3 bases found at 3' end remain unpaired ii) always have 5'CCA3' iii) amino acid is attached via ester bond: 3'-hydroxyl group of adenosine and carboxyl group of an amino acid

question

Messenger RNA (mRNA)

answer

-500-6000 nucleotides long -Carriers of genetic information (working copy of genome) -Transcription: pre-mRNA processing> 5' cap addition> splicing> editing> polyadenylation> transport> translation -Triplets: found on DNA -Codons: found on mRNA -Anticodons: found on tRNA

question

RNA polymerases

answer

RNA Polymerases: responsible for synthesis of RNA; need a primer and is synthesized in 5' to 3' direction; 3 types 1. RNA polymerase 1: makes rRNA 2. RNA polymerase 2: transcribes mRNA a) sensitive to alpha-amanitin in poisonous mushrooms: transcription inhibitor; prevents mRNA formation 3. RNA polymerase 3: transcribes tRNA Initiation phase: 1. interaction of RNA Polymerase and DNA 2. Promoters: recruit RNA polymerase to transcription start site 3. Located upstream/in front of gene needing to be transcribed; 2 regions: a) TATA box b) CAAT box 4. Transcription factors must bind to promoter region to begin transcription; 4 promoters: a) Leucine zipper b) Zinc finger c) Winged helix d) helix-loop-helix (HLH): protein dimerization Elongation phase: 1. phosphodiester bond 2. RNA polymerase translocates to the template strand and new nucleotide is added a) protein factors stabilize RNA polymerase: viral infections b) pre-RNA: once RNA is synthesized it must go through editing 3. Initially synthesized RNA contains: introns and exons but INTRONS need to be removed a) mutations: can arise at splice sites> abnormal protein formation 4. 5' cap: 7-methylquanidine residue added to mRNA 5' end

question

Initiation phase of RNA transcription

answer

Initiation phase: 1. interaction of RNA Polymerase and DNA 2. Promoters: recruit RNA polymerase to transcription start site 3. Located upstream/in front of gene needing to be transcribed; 2 regions: a) TATA box b) CAAT box 4. Transcription factors must bind to promoter region to begin transcription; 4 promoters: a) Leucine zipper b) Zinc finger c) Winged helix d) helix-loop-helix (HLH): protein dimerization

question

Elongation phase of RNA transcription

answer

Elongation phase: 1. formation of phosphodiester bridges between each nucleotide in an RNA molecule 2. RNA polymerase translocates to the template strand and new nucleotide is added

question

Termination phase of RNA transcription

answer

Termination phase: 1. dislocation of RNA polymerase from the DNA template done via: a) RNA secondary structure b) specific protein factors: stabilize RNA polymerase 2. Editing a) snRNAs: need these 5-proteins (U1, U2, U3, U4, U5) to form SPLICEOSOME> machine that edits mRNA b) pre-RNA: once RNA is synthesized it must go through editing c) Initially synthesized RNA contains: introns and exons but INTRONS need to be removed at splice sites i) mutations: can arise at splice sites> abnormal protein formation ii). 5' CAP: 7-methylquanidine residue added to mRNA 5' end iii). Poly A tail: >250 adenosine residues added (AAA...) at 3' end> prevents destruction

question

Translation (protein synthesis )

answer

Culmination of the transfer of genetic information stored as nucleotide bases in DNA to protein molecules which function in living cells. Protein folds into 3-D structure depending on its amino acid sequence once formed. -begins at 5' end of mRNA to 3' end -amino terminal end of protein: 5' end -carboxyl-terminal end: 3' end -3 nucleotides (codons) in MRNA: required to specify each amino acid

question

What are the 3 main RNA components necessary to translate RNA?

answer

1. tRNA: amino acids that are to be incorporated into the protein are attached to tRNA 2. Ribosomes: have rRNA and interact with mRNA so correct amino acid is incorporated into protein 3. mRNA: ribosome interacts mRNA

question

How many nucleotides are used for translation from mRNA?

answer

Only 4 nucleotides: A,C,G,U -these encode a protein containing up to 20 amino acids: not 1:1 ratio

question

Stop codons

answer

64 possible codons, but only 3 are used as stop codons: 1. UAA 2. UAG 3. UGA

question

Can more than one codon specify a specific amino acid?

answer

Yes, more than one codon can specify a specific amino acid 1. GUU, GUS, GUA, GUG: all code for valine 2. all amino acids except METHIONINE (AUG) and TRYPTOPHAN (UGG) have more than one codon

question

What marks the starting point for protein synthesis?

answer

All proteins create METHIONINE first

question

Mutations

answer

Cause different protein to be synthesized via: 1. insertions 2. deletions: cause FRAME SHIFT mutation

question

Machinery of protein synthesis

answer

1. Ribosomes have 3 sites where tRNA binds: a) A site: acceptor site (aminoacyl-tRNA site) b) P site: tRNA + newly synthesized protein c) E site: AMINOACYL-tRNA SYNTHETASE adds amino acids to tRNA and then exits ribosome i) Carboxyl group of amino acid is activated with ATP ii) tRNA + amino acid-AMP release

question

Define the Wobble Hypothesis

answer

1. Base pairing rules are the same as DNA except at 3rd position 3' base of codon a) Non-classic base pairing i) forms between this nucleotide and 5' base of anticodon ii) allows tRNA to incorporate DIHYDROURIDINE ii) not a perfect match so Wobble allows for non-classic base pairing to occur 2. Guanine residue at 5' position on anticodon can form base pair with either a) cytosine or a uridine residue b) G can bind to Uridine unlike Watson-Crick base pairing

question

Label the tRNA structure

answer

Label the structure

question

tRNA structure

answer

Labeled tRNA

question

What is the first step in the initiation phase of protein synthesis?

answer

A dissociated small subunit of ribosome (40s) forms a complex with a Eukaryotic Initiation Factor: 1. EIF 1A 2. EIF 2 3. EIF 3 Pre-initiation complex: EIF 2 + Met + tRNA + 40s + EIF 1A + EIF 3

question

What does EIF 4F do?

answer

1. Directs pre-initiation complex to 5' end of mRNA and binds a 5'cap

question

What does EIF 5 do?

answer

Directs Met+tRNA to P site -Large ribosomal unitl binds to small unit with Met -tRNA/mRNA complex -Scans mRNA until AUG (Met) code is found

question

What is the first step of elongation?

answer

Peptidyl transferase: forms peptide bond between amino groups; conveyor belt A site: growing peptide chain P site: end of growing peptide chain; forms bond with AA

question

Termination

answer

Occurs when A site of ribosome reaches mRNA stop codons Releasing factors recognize stop codons> release protein from tRNA

question

Chaperone

answer

Proteins responsible for folding newly synthesized protein into 3D shape 1. bind to expose hydrophobic regions of unfolded proteins 2. Prevent their interaction with each other by shielding interactive surfaces a) prevent from aggregating b) induce folding of molecule c) Heat shock proteins (HSP70): protective protein with cancer tx implications

question

How many histone proteins are there?

answer

8 histone proteins

question

What are the 2 classes of chromatin?

answer

1. Non-histone proteins: polymerases, hormone receptors, nuclear enzymes 2. Histones: Hi, H2A, H2B, H3, H4

question

Describe nucleosomes

answer

Octameric protein with 2 subunits each of H2A, H2B, H3 and H4

question

Describe the roles of telomeres

answer

1. Ends of each chromosome: telomeres 2. Consist of repeated DNA sequences: TTA, GGG a) long repeating unitls b) repair enzymes leave this alone c) TELOMERASE: catylic ribonucleoprotein that makes telomeres> adds repeats to 3' end using RNA template i) it is a REVERSE TRANSCRIPTASE: RNA to DNA

question

Describe telomerase

answer

Composed of 2 subunits that bring their own RNA template 1. Telomerase reversetranscriptase (hTERT) 2. HTR: telomerase RNA Protects terminal ends of chromosomes from fraying 1. protects ends of chromosomes from being processed as DNA strand breaks Telomerase inhibitors: prevent cancer cell division Telomerase inducers: anti-aging> cells can only divide 50-90 times and then G.O. phase

question

What is a kinetochore? What is a centromere?

answer

1. Spindle fibers bind here 2. During mitosis, spindle fibers attach to centromere in a specific protein region 3. Centromeres: binds central constricted parts of chromosomes and divides into 2 arms made of undefined repetitive DNA: location indicator for genes a) P arm: short arm b) Q arm: long arm

question

In what direction is DNA read and synthesized?

answer

DNA is read in a 3' to 5' direction but is synthesized in a 5' to 3' direction, which is called a complimentary strand.

question

What is the role of DNA polymerase in DNA replication?

answer

Catalyzes the formation of hydrogen bonds and makes phosphodiester bonds. It is the enzyme that copies and elongates DNA strand after primase forms a primer.

question

Geminin vs. MCM

answer

Geminin binds to newly formed DNA strands and prevents them from being replicated. MCMs coat DNA that need to be copied and prevents them from snapping back together.

STUDY

A Level Biology Thin Layer Chromatography

paper chromatography -identify unknown amino acids 17 terms

Tiffany Hanchett

17 terms

Preview

paper chromatography -identify unknown amino acids

question

what is the first thing you would do

answer

draw a pencil line near the bottom of a piece of chromatography paper and put a concentrated spot of the picture of amino acids on it (point of origin)

question

what is it best to do with the piece of chromatography paper

answer

best to carefully roll the pice of paper into a cylinder with the spot on the outside so it'll stand up

question

one you have added the point of origin and rolled the paper what would you do

answer

add a small amount of prepared solvent to a beaker and dip the bottom of the paper into it (not the point of origin)

question

what is the solvent you oddly use for amino acids

answer

mixture of butan-1-ol , glacial ethanoic acid and water

question

where should the dipping of the paper in the solvent be done

answer

in a fume cupboard cover with a lid to stop the solvent evaporating

question

what will happen as the solvent spreads up the paper

answer

the different amino acids move with it but at different rates so they separate out

question

what should you do once the solvents nearly reached the top of the paper

answer

take the paper out of the solvent and mark the solvent front(distance travelled by solvent ) with a pencil

question

once you have marked the solent front what can you do

answer

leave the paper to dry out before you analyse it

question

why won't you be able to see amino acids on the paper

answer

because they aren't coloured

question

what do you need to do to the amino acids before you are able to analyse them

answer

you have to spray the paper with ninhydrin solution to turn the amino acids purple

question

where should the spraying of ninhydrin be done

answer

in a fume cupboard a gloves should be worn

question

what does ninhydrin detect only

answer

proteins and amino acids

question

what is the Rf value (value of amino acid )

answer

ratio of distance travelled by a spot to distance travelled by the solvent

question

how do you work out Rf value

answer

distance travelled by spot /distance travelled by solvent

question

when measuring distance travelled by spot what should you do

answer

measure from point of origin to vertical centre of spot

question

how can you work out what was in the mixture

answer

by calculating the Rf value for each spot and looking each Rf value up in a database , or table of known values

question

as well as looking up the Rf value in a database how else could you work out what was in a mixture

answer

-you could compare your chromatogram to the chromatogram of a known mixture and identify the components that way -if two spots have travelled the same distance in the solvent , they will be the same molecule

STUDY

A Level Biology AP Biology Biology IB Biology Marine Chemistry

IB Biology Paper 1 – Fletcher – Topic 2: Molecular Biology 73 terms

Mike Bryan

73 terms

Preview

IB Biology Paper 1 – Fletcher – Topic 2: Molecular Biology

question

1. Which of the following are connected by hydrogen bonds? A. Hydrogen to oxygen within a molecule of water B. Phosphate to sugar in a DNA molecule C. Base to sugar in a DNA molecule D. Hydrogen to oxygen between two different molecules of water

answer

D. Hydrogen to oxygen between two different molecules of water

question

2. The graph below shows the effect of substrate concentration on enzyme activity. What conclusion can be drawn about section X of the graph? A. The enzyme has started to denature and the reaction slows down. B. The reaction has finished and the substrate has been used up. C. The enzyme is saturated and is working at its maximum reaction rate. D. Some of the enzyme has been consumed and the reaction has reached a plateau.

answer

C. The enzyme is saturated and is working at its maximum reaction rate.

question

3. Which type of molecule is shown in the diagram below? A. Peptide B. Carbohydrate C. Lipid D. Nucleic acid

answer

A. Peptide

question

4. The percentage of thymine in the DNA of an organism is approximately 30%. What is the percentage of guanine? A. 70% B. 30% C. 40% D. 20%

answer

D. 20%

question

5. What is denaturation? A. A structural change of a protein that results in the loss of its biological properties B. A change in the genetic code of an organism C. A change in the amino acid sequence of a protein causing a disruption of its 3D shape D. The process by which amino acids are broken down and ammonia is released

answer

A. A structural change of a protein that results in the loss of its biological properties

question

6. How do cells capture the energy released by cell respiration? A. They store it in molecules of carbon dioxide. B. They produce glucose. C. The energy is released as pyruvate. D. They produce ATP.

answer

D. They produce ATP.

question

7. What is the source of the oxygen released into the air as a product of photosynthesis? A. Chlorophyll B. Carbon dioxide only C. Water only D. Both water and carbon dioxide

answer

C. Water only

question

8. What property of water makes it a good evaporative coolant? A. High latent heat of evaporation B. Relatively low boiling point C. Volatility D. Transparency

answer

A. High latent heat of evaporation

question

9. A number of different proteins are involved in nerve function. Which of the following does not require a membrane protein? A. Active transport of sodium B. Diffusion of K+ C. Diffusion of the neurotransmitter across the synapse D. Binding of the neurotransmitter to the post-synaptic membrane into the cell

answer

C. Diffusion of the neurotransmitter across the synapse

question

10.What is the difference between galactose and lactose? A. Lactose is a disaccharide and galactose is a monosaccharide. B. Lactose is the product of anaerobic respiration in humans and galactose is the product of anaerobic respiration in yeast. C. Lactose is an enzyme and galactose is a hormone. D. Galactose is a sugar found in milk but lactose is not found in milk.

answer

A. Lactose is a disaccharide and galactose is a monosaccharide

question

11.Which type of light is least useful for photosynthesis in terrestrial plants? A. Blue B. Green C. White D. Red

answer

B. Green

question

12.How many molecules of water are required to completely hydrolyse a polypeptide made up of 23 amino acids? A. 11 B. 22 C. 23 D. 44

answer

B. 22

question

13.Which of the following is part of the process of cellular respiration? A. Changes in the volume of the thoracic cavity B. Exchange of gases across the surface of the alveoli C. Exchange of gases across the surface of capillaries D. Glycolysis

answer

D. Glycolysis

question

14.Which variable has the least effect on enzyme activity? A. Temperature B. Light intensity C. pH D. Substrate concentration

answer

B. Light intensity

question

15.Which substance in prokaryotes contains sulfur? A. DNA B. Phospholipids C. Proteins D. Antibiotics

answer

C. Proteins

question

16.Which describes these molecules correctly? I. and II. (diagram not included) A. ribose and amino acid B. glucose and amino acid C. ribose and fatty acid D. glucose and fatty acid

answer

D. glucose and fatty acid

question

17.What sequence of processes is carried out by the structure labelled X during translation? A. Combining with an amino acid and then binding to an anticodon B. Binding to an anticodon and then combining with an amino acid C. Binding to a codon and then combining with an amino acid D. Combining with an amino acid and then binding to a codon

answer

D. Combining with an amino acid and then binding to a codon

question

18.The diagram below shows a biochemical pathway in a yeast cell. Which of the following correctly identifies a compound in the diagram? A. I is fat. B. II is pyruvate. C. III is lactate. D. IV is carbon dioxide.

answer

B. II is pyruvate.

question

19.The following diagram shows a short stretch of DNA. What bases are indicated by labels Y and Z? Adenine --- (Y) Cytosine --- (Z) Y Z A. thymine adenine B. thymine guanine C. uracil guanine D. uracil adenine

answer

B. thymine guanine

question

20.A plant is exposed to increasing light intensity from very dim to bright light, while the carbon dioxide concentration and temperature are kept at an optimum level. What will happen to the rate of oxygen production? A. It will increase exponentially. B. It will remain constant. C. It will decrease to a minimum level. D. It will increase to a maximum level.

answer

D. It will increase to a maximum level.

question

21.In some people, hemoglobin always contains the amino acid valine in place of a glutamic acid at one position in the protein. What is the cause of this? A. An error in transcription of the hemoglobin gene B. An error in translation of the mRNA C. Lack of glutamic acid in the diet D. A base substitution in the hemoglobin gene

answer

D. A base substitution in the hemoglobin gene

question

22.What is a role of sulfur in living organisms? A. Formation of proteins B. Formation of carbohydrates C. Formation of teeth D. Transmission of nerve impulses

answer

A. Formation of proteins

question

23.Which molecules form the nucleotide marked in the diagram? A. phosphate, deoxyribose and nitrogenous base B. phosphorus, ribose and nitrogenous base C. phosphorus, deoxyribose and guanosine D. phosphate, ribose and guanine

answer

A. phosphate, deoxyribose and nitrogenous base

question

24.Which enzyme catalyzes the elongation of the leading strand? [Source: image from W K Purves, et al., (2003) Life: The Science of Biology, 4, Sinauer Associates (www.sinauer.com) and W H Freeman (www.whfreeman.com)] A. RNA polymerase B. Helicase C. DNA polymerase D. Ligase

answer

C. DNA polymerase

question

25.Which of the following is a function of cellulose in plants? A. Storage of fat B. Formation of mitochondria C. Storage of energy D. Formation of cell walls

answer

D. Formation of cell walls

question

26.Which of the following is the best definition of cell respiration? A. A process needed to use energy, in the form of ATP, to produce organic compounds B. A process used to provide oxygen to the atmosphere C. A controlled release of energy, in the form of ATP, from organic compounds incells D. A controlled release of energy in the production of food from organic compounds

answer

C. A controlled release of energy, in the form of ATP, from organic compounds incells

question

27.The graph below shows the effect of temperature on the separation of the strands in DNA to form single strands. The temperature at which 50% of the DNA is single-stranded is called the melting temperature (TM). What do the results show? A. When the temperature reaches 85°C there are no more double-stranded DNA molecules. B. When the temperature reaches 85°C the DNA strands start separating rapidly. C. A TM of 85°C means that DNA is not stable at room temperature (25°C). D. The separation of the DNA strands is directly proportional to the increase in temperature.

answer

B. When the temperature reaches 85°C the DNA strands start separating rapidly.

question

28.Which diagram best illustrates the interactions between water molecules?

answer

B. (connected by one O and one H)

question

29.What chemical reaction is taking place when a dipeptide becomes two amino acids? A. Condensation B. Hydrolysis C. Denaturation D. Polymerization

answer

B. Hydrolysis

question

30.The base ratios in the DNA and RNA for an onion (Allium cepa) are given below. Bases A / % G / % C / % T / % DNA 31.8 18.4 18.2 31.3 Bases A / % G / % C / % U / % RNA 24.9 29.8 24.7 20.6 What is the reason for the difference between these figures? A. DNA is only found in the nucleus but RNA is found throughout the cell. B. DNA is made entirely of double helix but RNA is not. C. In DNA, bases A and T are complementary but in RNA, bases A and C are complementary. D. RNA comes in three forms but DNA only comes in one form.

answer

B. DNA is made entirely of double helix but RNA is not.

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31.Which of the following will cause an enzyme to permanently lose its properties? I. Hydrolysis II. Freezing to -20°C III. Dissolving it in water A. I only B. II only C. I and II only D. I and III only

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A. I only

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32.What is lactase used for? A. It is used to make sugar-free milk. B. It hydrolyses lactose to glucose and fructose. C. It improves the digestion of milk by some people. D. It decreases the acidity of the milk.

answer

C. It improves the digestion of milk by some people.

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33.How can the rate of photosynthesis of a plant be directly measured? A. By measuring the rate of oxygen produced B. By measuring the rate of carbon dioxide produced C. By measuring the rate of plant growth D. By measuring the rate of light absorbed

answer

A. By measuring the rate of oxygen produced

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34.What is true of the source, products and optimum pH of the lipase found in the human digestive system? Source Products Optimum pH A. salivary glands fatty acids 8 B. stomach starch 2 C. pancreas fatty acids 8 D. liver amino acids 2

answer

C. pancreas fatty acids 8

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35.Which diagram represents the polarity of a water molecule?

answer

B O- H+ H+

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36.Which of these molecules is a disaccharide? A. Galactose B. Sucrose C. Cellulose D. Ribose

answer

B. Sucrose (fructose + glucose)

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37.What is a codon? A. A sequence of nucleotides on rRNA that corresponds to an amino acid B. A sequence of nucleotides on mRNA that corresponds to an amino acid C. A sequence of nucleotides on tRNA that corresponds to an amino acid D. A sequence of nucleotides on DNA that corresponds to an amino acid

answer

B. A sequence of nucleotides on mRNA that corresponds to an amino acid

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38.What happens as an enzyme becomes denatured? A. The enzyme works faster. B. The enzyme works slower. C. The enzyme can perform a new role. D. The enzyme can make the reverse reaction proceed faster.

answer

B. The enzyme works slower.

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39.What happens during the pathway of glycolysis? A. Glucose is broken down into pyruvate. B. Carbon dioxide is produced. C. More ATP is consumed than is produced. D. Lactic acid is produced.

answer

A. Glucose is broken down into pyruvate.

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40.What is light energy used for during photosynthesis? A. To produce carbon dioxide B. To produce water molecules C. To produce ATP D. To break down sugar molecules

answer

C. To produce ATP

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41.Which molecule is shown below? A. Glucose B. Galactose C. Ribose D. Sucrose

answer

C. Ribose

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42.Blood is a water-based transport medium. Which property of water makes it a good transport medium? A. High specific heat B. Transparency C. Versatility as a solvent D. It has its greatest density at 4°C

answer

C. Versatility as a solvent

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43.What is replicated by a semi-conservative process? A. Messenger RNA (mRNA) only B. Messenger RNA (mRNA) and transfer RNA (tRNA) only C. Messenger RNA (mRNA), transfer RNA (tRNA) and DNA only D. DNA only

answer

D. DNA only

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44.Which of the following processes produces CO2? I. Glycolysis II. Alcohol (ethanol) fermentation III. Lactic acid production A. I only B. II only C. I and II only D. I, II and III

answer

D. I, II and III

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45.Which of the following colours of light is absorbed the most by chlorophyll? A. Blue B. Green C. Yellow D. Orange

answer

A. Blue

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46.Which of the following chemical elements are part of biochemical molecules in living organisms? A. nitrogen, sulfur, phosphorus and iron B. lead, oxygen, carbon and phosphorus C. helium, carbon, sulfur and nitrogen D. silicon, helium, oxygen and iron

answer

A. nitrogen, sulfur, phosphorus and iron

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47.Which of the following is an organic compound made by all plants? A. Carbon dioxide B. DNA C. Lactose D. Oxygen

answer

D. Oxygen

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48.Which of the following graphs shows the relationship between substrate concentration and enzyme activity with a fixed concentration of enzyme?

answer

C. (exponential rise)

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49.Oxygen is produced during photosynthesis. What is the source of this oxygen inside the plant? A. Air spaces in the leaf B. Carbon dioxide C. Glucose D. Water

answer

D. Water

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50.Which of the following chemical elements are part of biochemical molecules in living organisms? A. nitrogen, sulfur, phosphorus and iron B. lead, oxygen, carbon and phosphorus C. helium, carbon, sulfur and nitrogen D. silicon, helium, oxygen and iron

answer

A. nitrogen, sulfur, phosphorus and iron

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51.Carbon, hydrogen, nitrogen and sulphur are elements found in living cells. Which is the least common? A. Carbon B. Hydrogen C. Nitrogen D. Sulphur

answer

D. Sulphur

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52.Which of the following terms correctly describe the molecule below? I. Monosaccharide II. Ribose III. Carbohydrate A. I only B. I and III only C. II and III only D. I, II and III

answer

B. I and III only

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53.A certain gene in a bacterium codes for a polypeptide that is 120 amino acids long. How many nucleotides are needed in the mRNA to code for this polypeptide? A. 30 B. 40 C. 360 D. 480

answer

C. 360 (120*3)

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54.What enzyme is used in transcription but not in translation? A. DNA polymerase B. Helicase C. Protease D. RNA polymerase

answer

A. DNA polymerase

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55.Which two colours of light does chlorophyll absorb most? A. Red and yellow B. Green and blue C. Red and green D. Red and blue

answer

D. Red and blue

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1 (a) State one example of a fibrous protein and one example of a globular protein. Fibrous protein: Globular protein:

answer

Fibrous protein: CollagenGlobular protein: hemoglobin

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1 (b) Compare the structure of fibrous and globular proteins.

answer

both are polypeptides globular proteins have tertiary structure fibrous proteins do not (may have extended secondary structure); globular proteins are rounded in shape fibrous proteins are elongated; globular proteins are (generally) soluble fibrous tend to be insoluble;

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1 (c) Amino acid polarity is an important factor in determining the functions of proteins. Explain the importance of polar and non-polar amino acids in membrane proteins.

answer

polar amino acids are soluble; non-polar amino acids are soluble; polar amino acids strongly hydrophilic and non-polar amino acids are hydrophobic; (help to) retain protein in position in the membrane; polar amino acids form hydrophilic channels in membranes; transmembrane proteins have polar amino acids on either side of the membrane;

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4. (a) Outline the bonding between DNA nucleotides.

answer

hydrogen bonds between nucleotides of complementary bases; covalent bonds between nucleotides between sugar/deoxyribose and phosphate;

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4. (b) Explain how chemical bonding between water molecules makes water a valuable coolant in living organisms.

answer

hydrogen bonding between water molecules; breaking (hydrogen bonds) removes heat; hydrogen bonds must break when water evaporates/vaporizes;

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4. (c) Describe the movement of water across membranes.

answer

osmosis / moves passively; from regions of low solute/high water potential/concentration to high solute concentration / low water potential/concentration; passes through protein channels/aquaporins/selectively-permeable membrane;

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4. (d) State the role of water in photosynthesis.

answer

water molecules undergo photolysis/are split by light energy; forms oxygen as a by-product; hydrogen helps power the fixation of carbon (into organic molecules);

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5. (a) State two functions of proteins, giving a named example of each.

answer

structure—collagen; transport—hemoglobin;enzymes/biological catalyst —amylase/protease/lipase/catalase; defence/immunity — immunoglobin/antibody; movement — actin/myosin; synthesis — ligase/DNA polymerase; hormonal communication — insulin/luteinizing hormone; MUST be proteinaceous food stores — casein in milk; pigments—opsin;

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5. (b) Explain the significance of polar and non-polar amino acids.

answer

polar amino acids have hydrophilic R groups, non-polar have hydrophobic R groups; non-polar amino acids in centre of water-soluble proteins stabilise their structure; non-polar amino acids cause proteins to remain embedded in membrane; polar amino acids on surface of proteins make them water-soluble; polar amino acids create hydrophilic channels/protein pores in membranes; enzyme active site specificity depends on amino acids present/polar and non-polar amino acids can play a role in substrate interactions at the active site;

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10. (a) Define active site.

answer

site on surface/portion of the enzyme/protein to which the substrate binds

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10. (b) Explain enzyme-substrate specificity.

answer

enzymes fit together with substrates similar to a lock and key; active site has shape that gives specificity; enzymes catalyze a reaction with a specific substrate; example of named enzyme and its substrate; substrate held precisely in (optimum) position to make/break bonds/carry out reaction / chemical interaction occurs between enzyme and substrate;

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11. (a) State the property of stem cells that makes them useful in medical treatment.

answer

has the ability to differentiate (into specialized tissue)

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11. (b) Explain how multicellular organisms develop specialized tissues.

answer

only some genes are expressed in each cell type/tissue; tissues therefore develop differently/become differentiated; example of differentiated cell and the function of tissues;

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11. (c) Outline some of the outcomes of the sequencing of the human genome.

answer

knowledge of location of human genes / position of human genes on chromosomes; knowledge of number of genes/interaction of genes / understanding the mechanism of mutations; evolutionary relationships between humans and other animals; discovery of proteins / understanding protein function / detection of genetic disease; leads to the development of medical treatment/enhanced research techniques; knowledge of the base sequence of genes/study of variation within genome;

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12. (b) State one difference between oxidation and reduction.

answer

oxidation is addition of oxygen while reduction is removal; oxidation is removal of H+, reduction is addition; oxidation is loss of electrons, reduction is gain;

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13. (a) State the type of bonds that (i) connect base pairs in a DNA molecule. (ii) link DNA nucleotides into a single strand.

answer

(i) hydrogen (ii) covalent / phosphodiester linkage

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13. (b) Distinguish between DNA and RNA nucleotides by giving two differences in the chemical structure of the molecules.

answer

DNA has deoxyribose, RNA has ribose; DNA has base T/thymine, RNA has base U/uracil; Do not accept double or single strands as chemical structure.

question

13. (c) Explain the role of transfer RNA (tRNA) in the process of translation.

answer

tRNA attaches to (specific) amino acid; tRNA (with amino acid) moves to the ribosome; anticodon of tRNA binds with codon of mRNA;

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A Level Biology AP Biology Biology Evidence For Evolution Evolutionary Biology Inheritance Of Acquired Characteristics

10.4 Biology Study Guide-Blackwell 5 terms

Andrew Hubbs

5 terms

Preview

10.4 Biology Study Guide-Blackwell

question

Evidence of Evolution...

answer

fossils, geography, embryology, anatomy

question

Vestigial structures seem to lack any useful function, or are at least no longer used for their original purpose. 3 examples are...

answer

wings of ostriches, the human appendix, snakes' tiny pelvic bones and strumplike limbs

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Feature that is similar in stucture in different organisms but has different functions

answer

homologous structure

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Feature that peforms a similar function in different organisms but is not similar in origin; is not evidence of a common factor

answer

analogous structure

question

Remnant of an organ or structure that had a function in an early ancestor

answer

vestigial structure

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