Deck 8: Microbial Genetics

Question 1

RNA polymerase uses ________ as a template to synthesize ________ .

A)RNA,proteins
B)RNA,DNA
C)DNA,RNA
D)DNA,proteins

Answer 1

C

Question 2

Genes with different information at the same locus are called _____.

A)chromosomes
B)homologs
C)plasmids
D)alleles

Answer 2

D

Question 3

During DNA replication:

A)the leading strand is synthesized in the 3' to 5' direction
B)the leading strand is synthesized discontinuously
C)the lagging strand is synthesized in the 5' to 3' direction
D)both strands are synthesized discontinuously

Answer 3

C

Question 4

During replication DNA is synthesized by _____.

A)DNA polymerase
B)RNA polymerase
C)ribosomes
D)ribozymes

Question 5

A plasmid is a/an _____.

A)extrachromosomal piece of DNA
B)chromosomal site to which genetic activity can be traced
C)body found in the cytoplasm that directs protein synthesis
D)molecule that carries the genetic message of the chromosomal DNA

Question 6

An mRNA molecule contains three nucleotide (triplet)units called _____.

A)amino acids
B)bases
C)codons
D)anticodons

Question 7

Segments of eukaryotic DNA that do not code for proteins:

A)are called introns
B)are found in all bacterial genes
C)can be considered by your immune system as enemy DNA
D)binds to proteins to form ribosomes

Question 8

Which statement is true

A)Proofreading that occurs during transcription changes the RNA into DNA.
B)Translation is a less accurate process than transcription.
C)Reverse transcription is a less accurate process than regular transcription.
D)Errors in replication can be proofread during transcription.

Question 9

Bacterial chromosomes:

A)must be present for a bacteria to stay alive and reproduce
B)are small segments of DNA that have the ability to move from one position to another
C)contain genetic information that is helpful but not necessary for survival
D)are always circular and only one is present in each bacteria

Question 10

The information carried by DNA is used to create a ________ which then moves to the ribosome for protein synthesis.

A)tRNA
B)rRNA
C)siRNA
D)mRNA

Question 11

In DNA,the base adenine always pairs with what other base

A)guanine
B)adenine
C)uracil
D)thymine

Question 12

Which of the following statements is true

A)During DNA replication the leading strand serves as template for replication of lagging strand.
B)Fragments on the lagging strand are joined together by DNA ligase.
C)A bacterial chromosome is made up of individual units called Okazaki fragments.
D)Two strands of double helix combine by base pairing in a parallel fashion.

Question 13

Replication results in the formation of what type of new molecule

A)DNA
B)RNA
C)Protein
D)Lipid

Question 14

Mutations:

A)when occurring on a particular Okazaki fragment can lead to different loci
B)often change a person's blood from type A to type AB
C)are responsible for heritable variations seen in progeny
D)occur only when the DNA is transmitted to a daughter cell

Question 15

Okazaki fragments make up part of the _____.

A)small ribosomal subunit
B)tRNA
C)lagging strand of newly synthesized DNA
D)mRNA

Question 16

After DNA replication of a bacterial chromosome,the new DNA contains:

A)2 newly synthesized strands of DNA copied from the original parent strands
B)one strand of parent DNA along with one newly synthesized strand
C)small segments of parent DNA interspersed with newly synthesized segments of DNA
D)two of these choices are true

Question 17

The process of ________ results in the synthesis of a new protein.

A)replication
B)transcription
C)translation
D)transversion

Question 18

Messenger RNA:

A)is formed in the 3' to 5' direction
B)is found only in prokaryotes
C)contains uracil instead of thymine
D)is synthesized using the enzyme ligase

Question 19

Bacterial genomes:

A)have rarely been sequenced as it takes a very long time.
B)only contain adenine,uracil,cytosine and guanine.
C)contain all the information for the structure and functioning of a cell.
D)when sequenced 100% of the genes are with known cellular function.

Question 20

A linear sequence of DNA nucleotides which provides the genetic information for a single characteristic is a _____.

A)chromosome
B)plasmid
C)gene
D)base pair

Question 21

In eukaryotes,transcription takes place in the ________ while translation takes place in the ________.

A)nucleus,nucleus
B)nucleus,cytoplasm
C)cytoplasm,nucleus
D)cytoplasm,cytoplasm

Question 22

An anticodon would be found in/on a ________ molecule.

A)mRNA
B)tRNA
C)the lagging strand
D)rRNA

Question 23

When an E.coli cell contains high levels of lactose,the lactose will bind with the _____.

A)repressor
B)operator
C)promoter
D)RNA polymerase

Question 24

In an enzyme catalyzed reaction that displays feedback inhibition,_____

A)excess substrate will inhibit the reaction.
B)excess product will inhibit the reaction.
C)the reaction continues at the same pace regardless of conditions in the cell.
D)excess product is broken down to create new substrate.

Question 25

In the lactose operon,which of the following is a protein

A)Repressor
B)Operator
C)Regulator
D)Promoter

Question 26

Which of the following properties are exclusive to tRNA

A)Combines with specific proteins to form ribosomes
B)Carries information from DNA for synthesis of a protein
C)Molecules contain an anticodon
D)Contains the nucleotide thymine

Question 27

A DNA mutation that results in no change in protein product produced is termed a:

A)missense mutation
B)nonsense mutation
C)silent mutation
D)frameshift mutation

Question 28

Which of the following properties are exclusive to mRNA

A)Combines with specific proteins to form ribosomes
B)Carries information from DNA for synthesis of a protein
C)Molecules contain an anticodon
D)Contains the nucleotide thymine

Question 29

Amino acids move from the cytoplasm to the ribosome with the help of _____.

A)mRNAs
B)tRNAs
C)siRNAs
D)rRNAs

Question 30

Which of the following properties are exclusive to rRNA

A)Combines with specific proteins to form ribosomes
B)Carries information from DNA for synthesis of a protein
C)Molecules contain an anticodon
D)Contains the nucleotide thymine

Question 31

In the lac operon RNA polymerase first binds to the:

A)promoter
B)operator
C)repressor
D)regulator

Question 32

________ refers to the specific characteristics displayed by an organism.

A)Genotype
B)Mutation
C)Phenotype
D)Genes

Question 33

tRNA anticodons serve as a link between ______.

A)DNA and mRNA
B)codons and anticodons
C)codons and amino acids
D)mRNA and rRNA

Question 34

Catabolite repression:

A)cells save energy by not making uneeded enzymes
B)doesn't allow for cells to prioritize consumption of multiple substrates
C)allows cell growth to continue even after the preferred nutrient is used up
D)two of these

Question 35

Which of the following statements about the genetic code is true

A)The first position of a codon determines the amino acid.
B)An amino acid can be specified for by more than one codon.
C)Nonsense codons contain no information.
D)Because DNA only contains four letters there are very few number of possible genes that can exist.

Question 36

The tryptophan (trp)operon is turned on (i.e.gene expression occurs)when:

A)there is a great deal of tryptophan in the cell
B)there is a lack of tryptophan in the cell
C)the trp operon is always turned on
D)the trp operon is always turned off

Question 37

Protein synthesis:

A)in bacteria can occur with several ribosomes attached to the same mRNA molecule
B)uses very little of a bacterial cell's energy
C)can occur at the same time as an mRNA is being transcribed
D)two of these

Question 38

With regard to the lac operon,which of the following is false under conditions of low (or no)lactose

A)The RNA polymerase cannot transcribe structural genes
B)The repressor is bound to the operator
C)Lactose is not bound to the repressor
D)RNA polymerase can bind to the promoter

Question 39

Inducible enzymes:

A)are synthesized continuously by the cell
B)are produced by genes that are always active
C)are synthesized by genes that are sometimes active and sometimes inactive
D)only exist in prokaryotic organisms

Question 40

A frameshift mutation occurs when:

A)an adenine is inserted into the DNA sequence of an organism
B)a thymine replaces a guanine in the DNA sequence of an organism
C)three new bases are inserted into the DNA strand
D)three bases are deleted from the DNA strand

Question 41

Which of the following is the anti-codon corresponding to methionine

A)AUG
B)GAC
C)CUG
D)UAC

Question 42

Mutagens such as 5-bromouracil cause mutations by:

A)substituting for one of the bases normally found in DNA
B)adding an alkyl group to a nucleotide
C)removing an amino group from a nucleotide
D)causing breaks in chromosomes

Question 43

Which statement about mutations is false

A)A mutation can alter the genotype of an organism without altering the phenotype.
B)Frameshift mutations are typically more serious than point mutations.
C)Spontaneous mutations are the result of exposure to mutagens.
D)Photoreactivation can take place in non-photosynthetic bacteria.

Question 44

Polymerase chain reaction:

A)allows for the rapid amplification of a billion copies of DNA without needing a living cell
B)can be applied to historic samples and to criminal investigations
C)requires oligonucleotides to cut DNA into smaller pieces
D)two of the above are true

Question 45

The fluctuation tests done by Luria and Delbruck showed that:

A)antibiotics induce the development of resistance in bacteria
B)the growth of bacteria fluctuates based on the concentration of antibiotics in the media
C)the concentration of antibiotics fluctuates in response to the number of bacteria in a sample
D)resistance to antibiotics occurs spontaneously in bacteria

Question 46

The Ames test is used to determine if a chemical:

A)increases the rate at which a bacterial cell divides
B)decreases the number of cells in a culture
C)induces mutations in a cell's DNA
D)decreases the ability of a cell to photosynthesize

Question 47

Pyrimidine dimers are a type of mutation most commonly caused by:

A)alkylating agents
B)deaminating agents
C)ultraviolet light
D)acridine

Question 48

Spontaneous mutations are:

A)caused by chemicals such as acridine and caffeine.
B)caused by physical agents such as ultraviolet light or x-rays.
C)the result of errors in the base pairing of nucleotides during replication.
D)occur at a rate higher than the rate of induced mutations.

Question 49

In order for beta-galactosidase,permease and transacetylase to be produced,____ can cause the operator to initiate transcription.

A)mRNA
B)lac operon
C)repressor proteins
D)RNA polymerase

Question 50

Photoreactivation:

A)repairs dimers in DNA using an endonuclease
B)uses light to activate repair enzymes
C)removes alkylating agents from bases
D)occurs when UV light causes mutations in DNA

Question 51

Organisms that have lost the ability to synthesize a particular enzyme and which require certain nutrients to be added to their medium to maintain growth are termed:

A)phototrophs
B)auxotrophs
C)prototrophs
D)autotrophs

Question 52

This molecule is used in the process of _____.

A)DNA replication
B)mitosis
C)meiosis
D)protein synthesis