Test Answers on Microbiology Lecture Exam #1 – Flashcards
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Unlock answers| Type of bacteria that lives in harsh conditions. |
| Archaea |
| Cells of animals, plants, fungi, and protist |
| Eukaryotic Cells |
| Contain membrane-bound organelles that compartmentalize the cytoplasm and perform specific functions. |
| Eukaryotic cells |
| No nucleus or other membrane-bound organelles. |
| Prokaryotic Cells |
| Contain double-membrane bound nucleus with DNA chromosomes. |
| Eukaryotic cells |
| Basic shape of cells |
| spherical, cubical, and cylindrical |
| Internal content |
| cytoplasm, surrounded by a membrane...DNA chromosome(s), ribosomes(synthesized protiens), metaboic capabilities. |
| 1st Characteristic of Life |
| Reproduction and heredity-genome composed of DNA packed in chromosomes; produce offspring sexually or asexually. |
| 2nd characteristic of life |
| Growth and development |
| 3rd characteristic of life |
| Metabolism-chemical and physical life processes |
| 4th chacteristic of life |
| Movement and/or irritability-respond to internal/external stimuli; self-propulsion of many organisms. |
| 5th characteristic of life |
| cell support, protection, and storage mechanisms - cell walls, vacuoles, granules and inclusions |
| 6th characteristic of life |
| Transport of nutrients and waste |
| Cellular structure and function is amazingly versatile and adaptable |
| Prokaryotic cell |
| Appendages, flagella, Pili, Fimbriae, Glycocalyx-capsule, slime layer |
| Prokaryotic cell (external) |
| Cell wall, cell membrane |
| Prokaryotic cell (cell envelope) |
| cytoplasmic matrix, ribosomes, inclusions(stored material), nucleoid/chromosome(DNA), actin cytoskeleton, endospore (has crust coating and is entirely different metabolic state) |
| Prokaryotic cell (Internal) |
| Because of their small size prokaryotic cells... |
| appear featureless and two dimensional when viewed with an ordinary microscope. |
| category of prokaryotes with pepidoglycan in their cell walls |
| Bacteria |
| organizing, classifing, and naming living things is called |
| Taxonomy |
| orderly arrangement of organisms into groups is called |
| classification |
| assigning names is called |
| nomenclature |
| determining and recording traits of organisms for placement into taxonomic schemes... |
| identification |
| Levels of Classification...1,2,3 |
1. Domain (Archaea, Bacteria, & Eukarya) 2. Kingdom 3. Phylum or Division |
| Levels of Classification 4,5,6 |
4. class 5. order 6. family |
| Levels of classification 7,8 |
7. Genus 8. Species |
| Plants, Animals, Fungi, Protists |
| Domian Eukarya |
| Cyanobactera, Chlamydias Spirochetes, Gram-positive bacteria, Endospore producers, Gram-negative bacteria |
| Domain Bacteria |
| Binomial (scientific) nomenclature |
Geives each microbe 2 names: Genus - which is captialized species - which is lower case Both of which are italicized or underlined |
| natural relatedness between groups of organisms is called |
| Phylogeny |
-All new species originate from preexisting species. -Closely related organism have similar features because they evolved from common ancestral forms. |
| Evolution |
| Methane producers, Prokaryotes that live in extreme salt, Prokaryotes that live in extreme heat |
| Domain Archaea |
| true bacteria |
| Bacteria |
| odd baceria that live extreme environments, high salt, heat, etc. |
| Archaea |
| Have a nucleus and organelles. |
| Eukarya |
| Process by which chemical substances (nutrients) are acquired from the environment and used in cellular activites. |
| Nutrition |
| Must be provided to an organism |
| Essential Nurtients |
These nutrients are required in large quantities; play principal roles in cell structure and metabolism. * Proteins, carbbohydrates |
| Macronutrients |
The nutrients are required in small amounts; involved in enzyme function and maintenance of pretein structure. *Manganese, zinc, nickel |
| Micronutrients or trace elements |
Contain carbon and hydrogen atoms and are usually the products of living things. *Methane (CH4), carbohydrates, lipid, proteins, and nucleic acids |
| Organic nutrients |
Atom or molecule that contains a combination of atoms other than cargon and hydrogen (no carbon) *Metals and their salts, gases, and water |
| Inorganic nutrients |
70% water Proteins 96% of cell is composed of these 6 elements:
|
Carbon Hydrogen Oxygen Phosphorous Sulfur Nitrogen
|
| Must obtain carbon in an organic form made by other living organisms such as proteins, carbohydrates, dipids, and nucleic acids. |
| Heterotroph |
| Producers of an Eco-system |
| Autotroph |
an organism that uses CO2 an inorganic gas as its carbon source. *Not nutritionally dependent on other living things. |
| Autotroph |
| Organic compounds that cannot be synthesized by an organism because they lack the genetic and metabolic mechanisms to synthesize them |
| Essential Organic Nutrients |
| Growth factors must be provided as a nutrient such as... |
| Essential amino acids and vitamins |
| Sources of Essential Nutrients |
Carbon sources (Heterotroph and Autotroph) |
| Main determinants of nutritional type are: |
Carbon source-heteroph and autotroph Energy source-chemotroph and phototrophs |
| gain energy from chemical compounds |
| Chemotroph |
| gain energy through photosynthesis |
| Phototrophs |
| Photoautotroph is an autotroph that gets its CO2 from what energy source |
Sunlight ex: organisms, such as algae, plants, cyanobacteria |
| Chemoautotroph is an autotroph that gets it CO2 from what energy source |
Simple inorganic chemicals ex: Only certain bacteria, such as methanogens, deep-sea vent bacteria |
| Chemoheterotroph is an Hetetotroph/Organic that get its energy source from |
Metabolic conversion of the nutrients from other organisms ex: Protozoa, fungi, many bacteria, animals |
| What is a Saprobe (Chemoheterotroph) energy source |
Metabolizing the organic matter of dead organisms ex: Fungi, bacteria (decomposers) |
| What is a Parasite (Chemoheterotroph) energy source |
Utilizing he tissues, uids of a live host ex: Various parasites and pathogens; can be bacteria, fungi, protozoa, animal. |
| A Photoheterotroph (Hetertroph/organic) that gets its energy from |
Sunlight or organic matter ex: Purple and green photosynthetic bacteria |
| Photoautotrophs survive by |
Oxygenic photosynthesis and Anoxygenic photosynthesis |
| Chemoautotrophs (lithoautotrophs) survive |
| totally on inorganic substances |
| Methanogen is a kind of chemoautotroph that... |
| produce methane gas under anaerobic conditions |
| Majority of Heterotrophs are chemohetertrophs which survive on... |
| Aerobic respiration |
Free-living microoorganisms that feed on organic detritus from dead organisms *Opportunistic pathogen *Facultative parasite are called: |
| Saprobes |
They derive nutrients from host *Pathogens *Some are obligate parasites |
| Parasites |
| Type of transport that does not require energy; substances exist in a gradient and move from areas of higher concentration toward areas of lower concentration: |
| Passive transport |
| List types of passive transports: |
| Diffusion, Osmosis, and Facilitated diffusion |
| moves down concentration gradient |
| Diffusion |
| diffusion of water |
| Osmosis |
| requires a carrier |
| Facilitated diffusion |
| Type of transport that requires energy and carrier proteins: gradient independent: |
| Active transport |
| transported molecule chemically altered |
| Group translocation |
| endocytosis (moves into the cell), exocyosis (goes outside fo the cell), pinocytosis |
| Bulk transport |
| 6 I's; of culturing microbes |
| Inoculation, Isolation, Incubation, Inspection, Information gathering, and Identification |
| Introduction of a sample into a containter of media to produce a culture of observable growth is called |
| Inoculation |
| Seperating one species from another is called |
| Isolation |
| Under conditions that allow growth... |
| Incubation |
| Isolation techniques include: |
Streak plate technique Pour plate technique Spread plate technique |
| Media can be classified by what three state: |
Physical state Chemical composition Functional type |
| liquid (TSB), simisolid, and solid |
| Physical state |
| synthetic (chemically defined) and nonsynthetic (complex) |
| Chemical composition |
| general purpose, enriched, selective, differential, anaerobic growth, specimen transport, assay, enumeration |
Functional type (Purpose of Medium) |
| Type of media that can be chemically defined is called |
| Synthetic |
| Type of media that is complex and is not chemically defined |
| Nonsynthetic |
| liquid medium containing beef extract and peptone |
| Nutrient broth |
| solid media containing beef extract, peptone (which is a partial digested protien), and agar |
| Nutrient agar |
| The most commonly used solidifying agent is called |
| Agar |
| A complex polysaccharide (sugars) isolated from red algae |
| Agar |
| Agar is solid at room temperature, liquiefies at boiling (100 C), and does not re-solidify until it cools at____ |
| 42 C |
| What does Agar do? |
| Provides framework to hold moisture and nutrients and is not digestivle for most microbes. |
| Media that contains pure organic and inorganic compounds in an exact chemical formula |
| Synthetic |
| Media that contains at least on ingredient that is not chemically definable. |
| Complex or nonsynthectic |
| Media that grows a broad range of microbes, usually nonsynthetic. |
| General purpose media |
| Media that contains complex organic substances such as blood, serum, hemoglobin, or special growht factors required by fastidious (hard to grow) microbes. |
| Enriched Media |
| Contains one or more agents that inhibit growth of some microbes and encourage growth of the desired microbes. |
| Selective Media |
| Allows growth of several types of microbes and displays visible differences amound thos microbes. |
| Differential Media |
| Contains a substance that absorbs oxygen or slows penetration of osygen into mediam; used for growing anaerobic bacteria. |
| Reducing medium |
| Contains sugars that can be fermented converted to acids, and a pH indicator to show this reaction. |
| Carbohydrate fermentation medium |
| Temperature-controlled chamber |
| Incubation |
| observation; macroscopic and microscopic |
| Inspection |
| grows only single known species of microorganisms |
| Pure culture |
| hold two or more identified species or microoorganisms |
| Mixed cultures |
| once pure or mixed uclture that has unwanted microbes growing |
| Contaminated culture |
| macroscopic and microscopic appearance, biochemical test, genetic characteristics, immunological testing |
| Identification |
| What two way are potentially hazardous cultures and specimens disposed? |
-Steam Sterilization (Autoclave) -Inceneration (Burning) |
| Division of bacterial cells occurs mainly through |
| Binary fission |
| Parent cell enlarges, duplicates its chromosome, and forms a central transverse septum dividing the cell into two daugher cells.; This is called |
| Binary Fission |
| Time requied for a complete fission cycle is called the |
| generation or doubling time |
| Each new fission cycle increases the population by a factor of |
| 2-exponential growth |
| Formula for calculating population size over time: |
Nf = (N1)2n ; Nf total # of cells in the population N1 is starting number of cells Exponentn denotes generation time 2n number of cells in that generation |
| In laboratory studies, population typically display a predictable patter over time called |
| growth curve |
| Stages in the normal growth curve include: |
| Lag Phase, Exponential growth phase, Stationary phase, and Death phase |
| "flat" period of adjustment, enlargement; little growth is called |
| Lag Phase |
| A period of maximum growth withll continue as long as cells have adequate nutrients and favorable environment. |
| Exponential growth phase |
| Rate of cell growth equals rate of cell death caused by depleted nutrients and O2, excretion of organic acids and pollutants. |
| Stationary phase |
| As limiting factor intensify, cells die exponentially. |
| Death phase |
| Degree of cloudiness, turbidity, reflects the relative population size.; This is called |
| Turbidometry |
| Getting a viable colony count or direct cell count of all cells present; automated or manual is called |
| Enumeration of bacteria |
| What can pick up fine degrees of difference in turbidity? |
| Spectrophotometer |
| Evenly cloudy thoughout |
| uniform fine turbidity |
| produces a type of surface membrane |
| pellicle |
| appears to clump (suspended chunks or pieces) |
| Flocculent |