question

genome

answer

all DNA present (chromosome + plasmids) the cells entire genetic component including both its genes and the nucleotide sequences that link genes together.

question

nucleic acids are polymers of basic building blocks called ______________.

answer

nucleotides

question

each nucleotide is made up of a __________ attached to a __________ which is intern made up of a pentose sugar.

answer

phosphate attached to a nucleoside

question

comp base pairs

answer

DNA
thymine-adenine
guanine-cytosine

RNA
uracil- adenine
guanine-cytosine

question

each new DaughterDNA is composed of

answer

one original strand
one new strand

question

dan polymerase replication adds in one direction

answer

5' to 3'

question

laggin strand vs leading strand

answer

laggin strand synthesized in segments
lead- all at once

question

DNA>complement DNA>mRNA>TrNA> codons

answer

1.dna template is converted to complement DNA
2. the original dNA template is used to code mRNA (opposites, T is now U)
3. now use the mRNA to code the tRNA (opposites, T is still U)

question

plasmids

answer

extra chromosomal pieces of DNA
1. replicate independently of the chromosome
2. nonessential genetic material

question

the central dogma

answer

explains the flow of information in a cell (info exists in DNA)

question

transcription

answer

uses DNA and makes RNA

question

translation

answer

process of translation uses RNA and produces the protein

question

what determines the genotype

answer

all DNA in cell determines the genotype

question

what determines phenotype

answer

all protein in cell determines phenotype of cell (their abilities)

question

phenotype is determined by _____________

answer

genotype

question

the abilities of a cell determines its

answer

phenotype

question

we can see a different phenotype without genotype being altered by ?

answer

regulating gene expression

question

what does it mean to say that a gene is being expressed?

answer

transcription and translation are taking place *if the gene is expressed we are seeing evidence of the phenotype *

question

when transcription and translation are taking place this means the __________ is being _______________

answer

gene is being expressed

question

what can alter the phenotype without changing genotype?

answer

gene expression

question

importance of regulation of genes (gene expression)

answer

energy is conserved when a cell does not need to make a particular protein

question

quorum sensing

answer

cells secrete quorum sensing molecules into their environment and other cells detect these signals so as to measure their density. when population size reaches a particular density, gene expression is turned on.

question

vibrio vulnificus
why is it necessary for v vulnificus to turn on different genes when the microbe invades a human?

answer

a gram negative pathogen found in estuarine environments (prefers to grow where salt meets freshwater) it causes wound infection and food bourne infections SHELLFISH

it is necessary for them to turn on different genes when the microbe invades humans because the host is different now so it must turn on genes allowing it to survive. (ex of chaningin phenotype without genotype)

question

mutations

answer

changes to the DNA
spontaneous, or induced (caused by exposure to something),

question

mutagens

answer

cause induced mutations (UV light or radiation for example)

question

pyrimidine dimers (thymine dimers)

answer

caused by UV light exposure
-wherever there are adjacent thymines, UV light causes thymines to bond to each other instead and breaks bond to adenine
-BOND BETWEEN A AND T ARE BROKEN
-T BONDS TO ANOTHER T INSTEAD
-can result in death, or simple change of phenotype
-depends what part of info is interrupted
-THIS OCCURS IN HUMAN CELLS!

question

DNA repair

answer

most cells have DNA repair mechanisms so we do not always see phenotypic change or cell death when a mutation occurs

1. light repair- enzyme activated in light that will go in and cut out thiamine dimer and fix it

2. dark repair- could occur in light or dark, not light activated, enzyme comes in and cuts out dmaged DNA and fixes thiamine dimer

question

gene transfer types

answer

vertical- process of asexual binary fission, parent cell gives genetic material to offspring it forms. offspring identical genetically to parent.

horizontal- once cells have been made, these cells have the potential to exchange genetic material. there are three types.

question

vertical gene transfer

answer

process of asexual binary fission, parent cell gives genetic material to offspring it forms. offspring has identical genetic material

question

horizontal gene exchange (3 types)

answer

horizontal- once cells have been made they may exchange genetic material

1. transformation- recipient cell take up DNA from environment such as DNA released by dead organisms. transformations from harmless to deadly are possible. smooth cells of donor make a capsule and rough cells of recipient does not make capsule so the rough cells take in dan from smooth cells and incorporate it into its own data.

recipient cell/smooth cell binds to a piece of DNA and take DNA into cel and incorporate that DNA into its own (GENETICALLY ALTERED)

requirements for transformation: DONOR CELL MUST BE DEAD, dan fragments in environment. RECIPIENT CELL MUST BE COMPETENT/able to bind to DNA and take DNA in (THIS IS CALLED COMPETENCY)
experiment: streptococcus (one has capsule, one does not) (this is a genetic difference) the encapsulated cells will kill mouse, cell without capsule will not kill cell. when dead encapsulated cells are given to a mouse, mouse lives. when he mixes dead encapsulated cell with living non encapsulated cell and gives it to the mouse, mouse dies DUE TO TRANSFORMATION (recipient cell is genetically altered by donor cell DNA even though the donor cell is dead)

2. transduction- a mistake in the lytic cycle (performed by bacteriophage). in transduction the first cell infected is the donor cell because the lytic cycle results in the rupture of the donor cell. in lytic cycle to host cell chromosome gets degraded and synthesis of viral parts begin, then assembly (cytoplasm contains donor cell and viral DNA so sometimes the bacterial DNA accidentally gets put into the capsid instead of the viral DNA. *mistake one has bacterial DNA (host cell) *at end of transduction recipient cell possesses donor cell DNA* bacteriphage must be present so it will take place

3. conjugation- conjugation requires contact between donor and recipient cell. It is mediated by pili which are thin protinaceous tubes on surface of cell. Gene that codes for pili is located on a plasmid called an F fertility plasmid. cells containing this are called F+ cells and they are the DONORS in conjugation. F- cells lack an F plasmid and therefor have no pili.1. sex pills attaches donor and recipient2.single strand of F plasmid DNA transfers to the recipient beginning with a section called origin of transfer. The F- recipient then synthesizes complementary strand of F plasmid DNA, becoming F+ cell. the donor also synthesizes a complementary strand restoring its complete plasmid.

* in some bacterial cells an F plasmid does not remain independent in the cytosol but instated integrates at a specific DNA sequence in the cellular chromosome. they are called HfR (high frequency of recombination) cells. they can conjugate with an F- cell. After the F plasmid has integrated and Hfr and F- cells join via pilus, DNA transfer begins at the origin of transfer of the F plasmid, carrying with it one copy of the donor's chromosome. **** in most cases movement breaks the intercellular connection before an entire donor chromosome is transferred. when the recipient only receives a portion of the F plasmid, it remains an F- cell but it also squires some chromosomal genes from the donor. recombination can integrate the donor DNA into the recipient's chromosome. the recipient is now a recombinant cell that contains its own genes as well as some donor genes. ***conjugation ENDS with pieces of F PLASMID and donor DNA in recipient cell, cells synthesize complementary DNA strands.

question

competency

answer

ability to bring in DNA fragment

question

what do nucleotides form together to make?

answer

nucleic acids (polymers of nucleotides) (RNA AND DNA)

question

how is a nucleotide structured

answer

it is made up of a phosphate attached to a nucleoside (which is made up of pentose sugar)

question

nucleotides are the basic building blocks of

answer

nucleic acids/ RNA DNA

question

nucleic acids types

answer

RNA AND DNA

question

a nucleoside is made up of

answer

pentose sugar

question

competency

answer

the recipient cells ability to bind to DNA from the donor cell (in transformation)

question

is it the template or complementary strand of DNA which is used to make the mRNA?

answer

template

question

point mutations, silent mutations,(also inversion, duplication, or transposition)

answer

point- just a single nucleotide base pair affected (substitution and frame shifts) (also known as insertions and deletions) (substitution is changing the letter, insertion and deletion produce more drastic affects on multiple codons

silence- no change because of redundancy in the genetic code

question

smooth cells have _____________ and are the _____ cell

answer

capsule (rough cells don't)
DONOR CELL
(rough cell=recipient)

question

what is the one requirement for transduction

answer

bacteriophage must be present

question

what is the one requirement of transformation

answer

donor cell must be dead
recipient must be competent

question

conjugation requirements

answer

3 requirements for conjucation:
one cell must posses F factor
two cells (donor and recipient) are opposite mating types (F+ and F-)
two cells must be in contact with eachother/ attach

question

in HFR cell conjugation what does the recipient cell receive first ?

answer

1/2 the F factor, then some genetic material

question

how can you interrupt conjugation?

answer

keep flask shaking, remove F factor

question

what happens in horizontal gene transfer, transformationwhich cell is genetically altered
what are the requirements

answer

a capsulated smooth cell DONATES dna to a non encapsulated Recipient rough cell that brings it in and incorporates it into its own DNA

the recipient is genetical altered

requirements:
1. donor cell must be dead with DNA fragments in environment
2. recipient cell must be competent

question

what is transduction? (horizontal gene transfer)

answer

a mistake in the lytic cycle resulting in bacterial DNA being placed in capsid instead of the intended viral DNA, this allows bacterial DNA to be transferred from one bacterial cell to another via a virus. (it can become integrated into recipient bacterial cell chromosome thereby transferring genes to the recipient)

*this is how antibiotics become useless due to transfer of resistant genes between bacterial cells

requirements:
1. bacteriophage must be present

question

what is conjugation? (F+ F- type)

answer

the transferring of DNA between bacterial cells by use of pili. A plasmid known as the F factor, or fertility factor, is required by the donor cell for conjugation to happen. The F+ donor cell produces a pilus which attaches it to the F- recipient cell .(F factor codes for pilus) F factor initiates its own replication once cells are attached and sends it to the recipient cell. Now it has become F+ cell.
*if conjugation is interrupted not all of F factor will be transferred and the recipient cell will contain some F factor but will still be F-

F+= contains F factor
F-= doesn't have F factor

requirements1. one cell must posses F factor
2. two cells (donor and recipient) are opposite mating types (F+ and F-)
3. two cells must be in contact with each other/ attach

question

what does the F factor genetic material allow for

answer

the creating on a pilus

question

what is the phenotypic change for the recipient cell in conjugation?

answer

it has gained the F factor

question

what is the HFr and F- conjugation?

answer

Same as F+ F- conjugation except the F factor DOES NOT EXIST AS PLASMID! it is part of the host cell chromosome and has integrated. F factor still initiates replication when cells attach, but the f factor is in the chromosome so its origin of replication is in the center meaning what is transferred first is the first 1/2of the F factor and then the chromosome gets replicated. The recipient cell remains F- because not whole F factor was received. (rarely becomes F+)(still can be future recipient in conjugation again)

question

what are cells called with F factor as part of the chromosome?

answer

HFR cells

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