Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Prokaryotic Molecular Genetics > PMG Final > Flashcards

PMG Final Flashcards

1
Q

A mutation always causes a mutant phenotype. T or F

A

Fasle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

A messenger is 336 nucleotides long, including the initiator and termination codons. The number of amino acids in the protein translated from this mRNA is

A

111

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

A spontaneous mutation usually originates as an error in

A

DNA replication

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

A ____ mutation affects the phenotype only under certain conditions.

A

conditional

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Changing the codon AGC to AGA represents a ____ mutation.

A

nonsense

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

A point mutation that changes a codon specifying an amino acid into a stop codon is called a

A

nonsense

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

The enzyme that creates a short RNA oligonucleotide at initiation sites where replication is to be carried out is
called

A

Primase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Gram-negative: have double cell membrane. T or F

A

True

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Nucleotides in each strand are linked by 5’-3’ phosphodiester bonds. T or F

A

true

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

DNA synthesis on the lagging strand is continuous. T or F

A

False

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

n the lagging during the DNA synthesis the Okasaki fragments are synthesized. T or F

A

True

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Bacteria have one circular chromosome, main genome (which carries housekeeping genes). To or F

A

True

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

The replication of the bacterial chromosome is unidirectional

A

False

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What relaxes strands

A

topoisomerase or girase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What opens strand and acts as guide for primase on both strands

A

Helicase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What keeps the strands apart during the replication process

A

Single binding proteins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What synthesizes primer sequences that are used by DNA polymerase III

A

Primase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What extends strands only in 5’ 3’ direction, thus one strand is continuous and one is in short
fragments (Okazaki fragments)

A

DNA Polymerase 3

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Replication continues until the replication fork enters a region of the chromosome called

A

Ter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Partitioning of the chromosome: is the distribution of one daughter chromosome to each of the two daughter cells. T or F

A

True

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

RNA which is able to pick up a specific amino acid, transfers it to ribosomes

A

tRNA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

is synthesized complementary to a gene and subsequently translated into a polypeptide or protein at ribosomes

A

mRNA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Below is the schematic representation of _______. Indicate the function its sub-units (show it below)

A

RNA polymerase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Promoter is a nucleotide sequence up stream of the gene to which RNA polymerase binds at the initiation of transcription. T or F?

A

True

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

___ is where an aminoacyl-tRNA first attaches

A

site A or acceptor or aminoacyl site

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

The peptide bond is formed by a ribozyme, called

A

peptidyl transferase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

___ is where the growing amino acid chain is temporarily being held by a tRNA as the next codon in the mRNA is being read.

A

site P or peptide site

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

____ Break the covalent bond that holds the finished protein to the terminal tRNA.

A

Release factors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Sec YEG : proteins that assist the non-covalent folding/unfolding. T or F

A

True

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Which mRNA codes for the following polypeptide?
met arg ser leu glu
a) 3’-AUG CGU AGC UUG GAG UGA-5’

b) 3’-AGU GAG GUU CGA UGC GUA-5’
c) 5’-AUG CGU AGC UUG GAG UGG-3’
d) 1’-AUGCGUAGCUUGGAGUGA-3’
e) 3’-AUGCGUAGCUUGGAGUGA-1’

A

c) 5’-AUG CGU AGC UUG GAG UGG-3’

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What is the consequence of a nonsense mutation?

A

Introduces a stop codon

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

A transition is a point mutation in which a purine is replaced by the other purine (A for G or G for A) or a pyrimidine by the other pyrimidine (C for T or T for C). A transversion is a point mutation in which a pyrimidine is replaced by a purine or vice versa. Some point mutagens (mutagenic chemicals that cause point mutations) mainly cause transitions or mainly transversions or mainly frameshift mutations.

Gene A contains a frameshift mutation. To revert that mutation (change it back to normal or wild type) you would use a

A

Mutagen causing frameshifts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

A transition is a point mutation in which a purine is replaced by the other purine (A for G or G for A) or a pyrimidine by the other pyrimidine (C for T or T for C). A transversion is a point mutation in which a pyrimidine is replaced by a purine or vice versa. Some point mutagens (mutagenic chemicals that cause point mutations) mainly cause transitions or mainly transversions or mainly frameshift mutations.

To revert a transition mutation you would use a

A

mutagen causing transitions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

A transition is a point mutation in which a purine is replaced by the other purine (A for G or G for A) or a pyrimidine by the other pyrimidine (C for T or T for C). A transversion is a point mutation in which a pyrimidine is replaced by a purine or vice versa. Some point mutagens (mutagenic chemicals that cause point mutations) mainly cause transitions or mainly transversions or mainly frameshift mutations.

To revert a transversion mutation you would use a

A

mutagen causing transversions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

The lac operon is expressed when

A

glucose is low and lactose is absent.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

When in a complex with ________, the CAP protein binds to the CAP site and ________ the expression of the lac

operon

A

cAMP ; switches on

37
Q

In the absence of lactose, the lac repressor is

A

active and can bind to the operator.

38
Q

The inducer of the lac operon is an isomer of lactose. T or F

A

TRUE

39
Q

When RNA polymerase is bound to the lac promoter sequence, transcription of the lac operon is on. T or F

A

True

40
Q

The trp operon consists of ________ structural genes.

A

five

41
Q

In the absence of tryptophan, the trp repressor is

A

inactive and cannot bind to the operator.

42
Q

In the presence of tryptophan, tryptophan binds to the

A

trp repressor.

43
Q

In the presence of tryptophan, transcription of the trp operon is on. T or F

A

False

44
Q

An operon is a group of genes that is under the control of a single operator site. T or F

A

False

45
Q

Cells of an E. coli strain that are trp - lac Z- met+ bio+ were mixed with cells of an E. coli strain that are trp + lac Z + met- bio- and cultured for several hours. Then cells were removed, washed, and transferred to minimal media containing
lactose as the only sugar source. A few cells were able to grow on minimal media with lactose, and formed colonies. How
did these few cells become trp+ lac+ Z met+
bio+ ?

A

Conjugation

46
Q

How many lac Z genes were present in the cells described in the previous problem (11) that were able to grow on minimal media?

Cells of an E. coli strain that are trp - lac Z- met+ bio+ were mixed with cells of an E. coli strain that are trp + lac Z + met- bio- and cultured for several hours. Then cells were removed, washed, and transferred to minimal media containing
lactose as the only sugar source. A few cells were able to grow on minimal media with lactose, and formed colonies. How
did these few cells become trp+ lac+ Z met+
bio+ ?

A

Two, the lac Z- allele on the bacterial chromosome and the lac Z+ allele on the F’ episome.

47
Q

How would you describe the regulation of lactose metabolism in the cells described in problem 11 that were able to grow on minimal media with lactose as a nutrient?

Cells of an E. coli strain that are trp - lac Z- met+ bio+ were mixed with cells of an E. coli strain that are trp + lac Z + met- bio- and cultured for several hours. Then cells were removed, washed, and transferred to minimal media containing
lactose as the only sugar source. A few cells were able to grow on minimal media with lactose, and formed colonies. How
did these few cells become trp+ lac+ Z met+
bio+ ?

A

normal regulation of lactose metabolism.

48
Q

An E. coli strain that is lac Z is conjugated with E. coli cells carrying an F’ plasmid with the plac Oc lac Z DNA sequence on the episome. The Oc is a mutation of the lactose operator that is no longer able to bind the lac I gene product which codes for the lac repressor. How would the expression of the lac Z be regulated in the resulting cells that are diploid for the lactose regulatory region and the lac Z gene?

A

constitutive expression of lac Z+.

49
Q

An E. coli strain that is lac Z is conjugated with E. coli cells carrying an F’ plasmid with the plac Oc lac Z DNA sequence on the episome. The Oc is a mutation of the lactose operator that is no longer able to bind the lac I gene product which codes for the lac repressor. How would the expression of the lac Z be regulated in the resulting cells that are diploid for the lactose regulatory region and the lac Z gene?

Predict the phenotype of a lacI mutant.

A

The lac genes would be expressed continuously.

50
Q

An E. coli strain that is lac Z is conjugated with E. coli cells carrying an F’ plasmid with the plac Oc lac Z DNA sequence on the episome. The Oc is a mutation of the lactose operator that is no longer able to bind the lac I gene product which codes for the lac repressor. How would the expression of the lac Z be regulated in the resulting cells that are diploid for the lactose regulatory region and the lac Z gene?

If a second wild type or normal copy of the lacI gene (just lacI and not lacZ, lacY, or lacA) is introduced into the lacI mutant cell, what would be the phenotype of this partial diploid (also referred to as a merodiploid)?

A

The lac genes would be expressed efficiently only in the presence of lactose.

51
Q

An E. coli strain that is lac Z is conjugated with E. coli cells carrying an F’ plasmid with the plac Oc lac Z DNA sequence on the episome. The Oc is a mutation of the lactose operator that is no longer able to bind the lac I gene product which codes for the lac repressor. How would the expression of the lac Z be regulated in the resulting cells that are diploid for the lactose regulatory region and the lac Z gene?

Predict the phenotype of a lacI S or “super-repressor” mutant. A lacI S mutant synthesizes a repressor that cannot bind
to the inducer.

A

The lac genes would never be expressed efficiently.

52
Q

An E. coli strain that is lac Z is conjugated with E. coli cells carrying an F’ plasmid with the plac Oc lac Z DNA sequence on the episome. The Oc is a mutation of the lactose operator that is no longer able to bind the lac I gene product which codes for the lac repressor. How would the expression of the lac Z be regulated in the resulting cells that are diploid for the lactose regulatory region and the lac Z gene?

Predict how a lacI S mutant would be affected by the construction of a merodiploid that has a second normal copy of the lacI gene.

A

The lac genes would never be expressed efficiently.

53
Q

An E. coli strain that is lac Z is conjugated with E. coli cells carrying an F’ plasmid with the plac Oc lac Z DNA sequence on the episome. The Oc is a mutation of the lactose operator that is no longer able to bind the lac I gene product which codes for the lac repressor. How would the expression of the lac Z be regulated in the resulting cells that are diploid for the lactose regulatory region and the lac Z gene?

Predict the phenotype of an operator mutant (Oc) which would prevent the binding of the repressor.

A

The lac genes would be expressed continuously

54
Q

An E. coli strain that is lac Z is conjugated with E. coli cells carrying an F’ plasmid with the plac Oc lac Z DNA sequence on the episome. The Oc is a mutation of the lactose operator that is no longer able to bind the lac I gene product which codes for the lac repressor. How would the expression of the lac Z be regulated in the resulting cells that are diploid for the lactose regulatory region and the lac Z gene?

Predict the phenotype of a promoter mutant (lacP) which has a mutation in the promoter for the lac operon.

A

The lac genes would never be expressed efficiently.

55
Q

An E. coli strain that is lac Z is conjugated with E. coli cells carrying an F’ plasmid with the plac Oc lac Z DNA sequence on the episome. The Oc is a mutation of the lactose operator that is no longer able to bind the lac I gene product which codes for the lac repressor. How would the expression of the lac Z be regulated in the resulting cells that are diploid for the lactose regulatory region and the lac Z gene?

Predict the phenotype of a lacZ mutant, which has a mutation in the gene for β-galactosidase.

A

The production of β-galactosidase would be affected, but other protein products would be unaffected.

56
Q

An E. coli strain that is lac Z is conjugated with E. coli cells carrying an F’ plasmid with the plac Oc lac Z DNA sequence on the episome. The Oc is a mutation of the lactose operator that is no longer able to bind the lac I gene product which codes for the lac repressor. How would the expression of the lac Z be regulated in the resulting cells that are diploid for the lactose regulatory region and the lac Z gene?

Predict the phenotype of a lacY mutant, which has a mutation in the gene for lactose permease.

A

The lac genes would be expressed efficiently until the lactose supply in the cell is exhausted.

57
Q

DNA transformation involves the transfer of DNA via

A

naked DNA in solution

58
Q

When DNA from an ampicillin resistant organism is brought into an ampicillin sensitive organism by transformation
and the product is grown on agar containing ampicillin

A

only the transformed cells will grow

59
Q

In transformation, both strands of donor DNA enter the recipient cell. T or F

A

False

60
Q

Donor DNA is combined with recipient DNA by homologous recombination. T or F

A

True

61
Q

A bacterial cell that is able to take up naked DNA is said to be

A

competent

62
Q

Which of these describes a similarity between the lac and ara operons?

A) Expression of structural genes does not occur at high glucose concentrations.

B) lacI and araI both encode trans acting factors.

C) Binding of a regulatory protein is prevented in the presence of an inducer.

D) All of these are similarities.

E) None of these are similarities.

A

A) Expression of structural genes does not occur at high glucose concentrations.

63
Q

Attenuation of the trp operon:

A) Occurs when transcription is complete before translation begins.

B) Is mediated by the trp repressor protein.

C) Occurs in the presence of high levels of tryptophan.

D) All of the above.

E) None of the above.

A

C) Occurs in the presence of high levels of tryptophan

64
Q

A prophage is

A

phage DNA integrated into host cell genome

65
Q

One of the largest global regulatory systems in bacteria are

A

Catabolite-Sensitive Operons

66
Q

CAP contains an “activating region” that has been proposed to participate in direct protein-protein interactions with RNA polymerase and/or other basal transcription factors.

a) in the Lac operon
b) in the Trp operon
c) in all Catabolite-Sensitive Operons
d) in Ara operon
e) in Lac and Ara operons

A

c) in all Catabolite-Sensitive Operons

67
Q

Some Hsp are chaperones that direct the folding of newly-translated proteins. In heat shock, they bind to denatured proteins and either help to refold them into their inactive conformations or, if the protein is extensively denatured, chaperones target these proteins for destruction. T or F

A

False

68
Q

_____ protein may be a “cellular thermometer” that senses the change in temperature and induces the transcription of
heat shock genes

A

DnaK

69
Q

Sigma-32 binds to the RBS of its own mRNA and blocks access of the ribosome. T or F

A

True

70
Q

Immediately after a temperature increase

a)most of the DnaK will have to help renature unfolded proteins, thus making DnaK unavailable for binding
sigma-32. So free sigma-32 is more stable (less susceptible to protease digestion) and more active.

b) most of the DnaK will have to help renature unfolded proteins, thus making DnaK available for binding sigma-32. So free sigma-32 is less stable (less susceptible to protease digestion) and more active.
c) most of the DnaK will be available for binding sigma-32; therefore bound sigma-32 is more stable (less susceptible to protease digestion) and more active.

A

a)most of the DnaK will have to help renature unfolded proteins, thus making DnaK unavailable for binding
sigma-32. So free sigma-32 is more stable (less susceptible to protease digestion) and more active.

71
Q

Transcriptional Regulation during the development of a typical large DNA phage the ________________ products are responsible for regulation the transcription (turn on or off the transcription of other genes)

A

Regulatory

72
Q

In specialized transduction

a) requires a phage that uses the lysogenic cycle for reproduction

b) only certain bacterial genes can be transferred and these genes, as you will see, must exist on either side of the prophage
most of the DnaK will have to help renature unfolded proteins, thus making DnaK unavailable for binding
sigma-32. So free sigma-32 is more stable (less susceptible to protease digestion) and more active.

c) a phage that uses the lytic cycle for reproduction
d) Whatever piece of bacterial DNA happens to get packaged within the phage is the genetic material that will be transferred between cells.
e) A and B

A

e) A and B

73
Q

The use or alteration of cells or biochemicals to provide a useful product describes

A

Biotechnology

74
Q

Which of the technologies listed below is a valuable method for mass-producing drugs and other useful proteins?

a) recombinant DNA technology
b) transgenic technology

c) biotechnology
d) gene targeting

A

a) recombinant DNA technology

75
Q

Manufacturing recombinant DNA molecules involves cutting a gene from its normal location, inserting it into a circular piece of DNA from a bacterial cell, and then transferring the circle of DNA to cells of another species. Which of the tools below is used to cut the gene from its normal location?

a) restriction enzyme
b) plasmid
c) bacteriophage d) vector

A

a) restriction enzyme

76
Q

Manufacturing recombinant DNA molecules involves cutting a gene from its normal location, inserting it into a circular piece of DNA from a bacterial cell, and then transferring the circle of DNA to cells of another species. Which of the below describe the circular piece of DNA from a bacterial cell?

a) restriction enzyme
b) plasmid
c) bacteriophage
d) vector

A

B) plasmid

77
Q

Which gene transfer technique involves a tiny needle which is used to inject DNA into a cell lacking that DNA sequence?

A

microinjection

78
Q

The process of ____ involves the introduction of a gene into a cell where it exchanges places with its counterpart in the host cell.

A

Gene targeting

79
Q

Genetic engineering manipulates gene products at the level of the

A

DNA

80
Q

A cDNA version of a gene includes

A

codons for a mature mRNA.

81
Q

____ are used to select genes of interest from a genomic library.

A

DNA probes

82
Q

Sequence similarity searching algorithms like BLAST are based on the premise that if two sequences are similar then they are likely to be homologous. T or F

A

true

83
Q

A motif is a distinctive pattern of amino acids, conserved across many proteins, which gives a particular function to the protein. T or F

A

True

84
Q

Expression libraries are made with

A

Complementary DNA (cDNA)

85
Q

To understand the functions of genes we use reverse genetics and some of its tools are a) RNAi

b) Knockout study c) Microarray
d) a and b
e) a, b and c

A

e) a, b and c

86
Q

Which of the following tools of recombinant DNA technology is INCORRECTLY paired with its use?

a) Restriction endonuclease - production of DNA fragments for gene cloning
b) DNA ligase - enzyme that cuts DNA, creating sticky ends
c) DNA polymerase - copies DNA sequences in the polymerase chain reaction
d) Reverse transcriptase - production of cDNA from mRNA

A

B) DNA ligase - enzyme that cuts DNA, creating sticky ends

87
Q

The “Southern” technique involves:

A

The detection of DNA fragments on membranes by a radioactive DNA probe

88
Q

“Gene library” is a term used to describe:

A

b) Bacteria with plasmids containing DNA fragments representing the majority of the genetic information

Prokaryotic Molecular Genetics (13 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions