Deck 12: Control of Gene Expression

Question 1

β-galactosidase is encoded by the ___________.

A)y gene of the lac operon
B)z gene of the lac operon
C)a gene of the lac operon
D)y gene of the trp operon
E)z gene of the trp operon

Answer 1

B

Question 2

Which of the traits below is characteristic of the classical nuclear localization signals?

A)possession of large numbers of hydrophobic amino acids
B)possession of one or two short stretches of negatively charged amino acids
C)possession of one or two short stretches of positively charged amino acids
D)twisted backbones
E)double helical regions

Answer 2

C

Question 3

What is the name of the regulatory protein which binds to specific DNA sequences with high affinity and plays an important role in determining whether a genome segment is transcribed or not?

A)the operator
B)the terminator
C)the promoter
D)the repressor
E)the structural genes

Answer 3

D

Question 4

The operator is the site on the __________.

A)DNA where the repressor binds
B)DNA where DNA polymerase binds
C)DNA where reverse transcriptase binds
D)RNA where the repressor binds
E)ribosome where the polymerase binds

Question 5

What is the name of the proteins that make up the nuclear lamina and of what protein superfamily are they a member?

A)lamins, laminins
B)lamins, intermediate filaments
C)keratin, intermediate filaments
D)keratin, laminins
E)actin, microfilaments

Question 6

When a regulatory protein inhibits transcription, this is known as _________________.

A)positive control
B)negative control
C)averaged control
D)circumspect control
E)neutral control

Question 7

Which of the following does NOT accurately describe the contents of the nucleus?

A)viscous
B)amorphous
C)undistinguished morphology
D)crystalline
E)highly extended nucleoprotein

Question 8

What is the name of the site where RNA polymerase binds to the DNA prior to the beginning of transcription?

A)the operator
B)the terminator
C)the promoter
D)the repressor
E)the structural genes

Question 9

Which two monosaccharides combine to form lactose?

A)2 glucose molecules
B)glucose and galactose
C)galactose and fructose
D)2 galactose molecules
E)glucose and fructose

Question 10

The lac operon is an example of _______ operon.

A)a noninducible
B)a constitutive
C)an inducible
D)a repressible
E)an irrepressible

Question 11

According to the text, what is the single most important distinction between prokaryotes and eukaryotes?

A)the existence of the Golgi complex
B)the separation of the cell's genetic material from the surrounding cytoplasm
C)the existence of ribosomes
D)the centrioles
E)the lysosomes and peroxisomes

Question 12

A transport receptor that moves macromolecules from the cytoplasm to the nucleus is called _______.

A)an exhalin
B)an exportin
C)an importin
D)a transportin
E)a receptin

Question 13

Which site in a bacterial operon is adjacent to or overlaps with a promoter?

A)operator
B)terminator
C)activator
D)repressor
E)structural genes

Question 14

With what structure is the outer membrane of the nuclear envelope continuous?

A)Rough endoplasmic reticulum
B)Smooth endoplasmic reticulum
C)Golgi complex
D)the spindle
E)the plasma membrane

Question 15

How do allolactose and lactose differ?

A)They are composed of different sugars.
B)Allolactose has a negative charge, while lactose has a positive charge.
C)The type of linkage holding the two constituent sugars together differs between lactose and allolactose.
D)The order of the sugars is reversed in the two molecules.
E)The constituent sugars are both upside down in lactose and right-side-up in allolactose.

Question 16

A section of a bacterial chromosome in which genes for the enzymes of a particular metabolic pathway are clustered together in a functional complex under coordinate control is called ______.

A)an operator
B)an operon
C)a promoter
D)a repressor
E)an activator

Question 17

What is the name of the linkage than holds the lactose disaccharide together?

A)β-galactoside linkage
B)α-lipophilic linkage
C)β-glycosidic linkage
D)α-galactoside linkage
E)ester linkage

Question 18

What future goals are being considered for cellular engineering attempts to reprogram cellular behavior?

A)reprogramming developmental events so that all humans will reach a standardized height
B)reprogramming metabolism to eliminate obesity and diabetes
C)reprogramming surface receptor responses so that receptor binding might cause tumor cell destruction
D)reprogramming cellular receptors to eliminate infectious disease
E)all these options are actively being pursued and researched

Question 19

Digital logic relies on all of the following EXCEPT:

A)0,1 binary values
B)electronic circuits where voltage switches are ON or OFF
C)circuit output regulating input
D)AND gates where two input circuits must be active to generate activity past the logic gate
E)OR gates where either of two input circuits must be active to generate activity past the logic gate

Question 20

The thin filamentous meshwork that is bound by integral membrane proteins of the inner surface of the nuclear envelope in animal cells is called the _________.

A)basement lamina
B)basal lamina
C)nuclear lamina
D)nucleon
E)nuclear limulus

Question 21

What evidence suggests that while the XIST gene may be required to initiate X chromosome inactivation, it may not be required to maintain it from one generation to another?

A)Tumor cells do not maintain X chromosome inactivation from generation to generation.
B)Some tumor cells in women contain inactivated X chromosomes whose XIST gene has been deleted.
C)Some tumor cells in women contain inactivated X chromosomes whose XIST gene has been duplicated.
D)Some women have patches of cells in their retinas that are color blind and others that are not.
E)Some tumor cells in women have no X chromosomes.

Question 22

What evidence suggests that RNAi plays a role in heterochromatization?

A)Deletion of RNAi components impairs both methylation of histone H3K9 and heterochromatization.
B)Addition of RNAi components impairs both methylation of histone H3K9 and heterochromatization.
C)Deletion of RNAi components enhances both methylation of histone H3K9 and heterochromatization.
D)Mutation of RNAi components denatures both methylation of histone H3K9 and heterochromatization.

Question 23

What energy source is used to maintain the Ran-GTP gradient across the nuclear envelope?

A)energy released by ATP hydrolysis
B)a proton gradient
C)a H⁺ ion gradient
D)energy released by GTP hydrolysis
E)an electron gradient

Question 24

In a rare disease, individuals suffer from bone marrow failure due to the inability of this blood-forming tissue to produce a sufficient number of blood cells over a human lifetime. What is NOT a cause of this condition?

A)Individuals have greatly elevated telomerase levels.
B)Individuals have greatly reduced telomerase levels.
C)Individuals are heterozygous for the gene that encodes the telomerase RNA.
D)Individuals are heterozygous for the gene that encodes the telomerase protein subunit.

Question 25

What is thought to maintain X chromosome inactivation?

A)repressive histone modifications
B)RNA inactivation
C)DNA methylation
D)localized DNA denaturation
E)both repressive histone modifications and DNA methylation

Question 26

What experimental evidence suggests that the N-terminal tails of histones participate in the formation of higher-order chromatin structure?

A)The tails cause histones to denature.
B)The tails when acetylated cause the dissolution of the 30-nm fibers.
C)Chromatin fibers with histones lacking their tails cannot fold into higher-order fibers.
D)Chromatin fibers with histones possessing longer tails cannot fold into higher-order fibers.
E)Chromatin fibers lacking tails are shorter.

Question 27

Genes are physically moved to sites within the nucleus called _________, where the transcription machinery is concentrated and within which genes involved in the same response tend to become colocalized.

A)transcription homes
B)transcription sites
C)transcription factories
D)translation factories
E)nucleosynthetic locales

Question 28

Why was it initially expected that cloned animals might have a shorter life span?

A)The chromosomes of the donor nuclei had shortened telomeres.
B)The chromosomes of the donor nuclei had lengthened telomeres.
C)The egg cell had elevated telomerase.
D)The donor cell had elevated telomerase.
E)After transplant of the nucleus, telomerase levels climbed precipitously.

Question 29

What distinguishes the regulatory, noncoding RNA that is suspected of being responsible for X chromosome inactivation from other noncoding RNA molecules?

A)It is much larger than the other noncoding RNAs.
B)It is much smaller than the other noncoding RNAs.
C)It is more tightly coiled than the other noncoding RNAs.
D)It contains a higher content of uracil than the other noncoding RNAs.
E)It contains a higher content of adenine than the other noncoding RNAs.

Question 30

Which is NOT an example of an epigenetic phenomenon?

A)X chromosome inactivation
B)histone methylation patterns
C)sequence of distal promoter elements
D)localization of histone variant CENP-A
E)covalent modification of DNA

Question 31

Which of the following would be the most acceptable explanation for why cloned animals actually have telomeres of normal length on their chromosomes?

A)The telomeres were elongated before transfer to the egg by telomerase in egg cell cytoplasm.
B)The telomeres were elongated after transfer to the egg by telomerase in egg cell cytoplasm.
C)The telomeres were shortened before transfer to the egg by telomerase in egg cell cytoplasm.
D)The telomeres were shortened after transfer to the egg by telomerase in egg cell cytoplasm.
E)The telomeres were replaced prior to mitosis by DNA repair.

Question 32

What is the name of the gene responsible for the inactivation of the X chromosome?

A)INAC
B)XIST
C)1STX
D)IRS
E)XCHR

Question 33

When an importin α/β complex carries a protein destined to move into the nucleus, what does it bind to when it comes to the outer surface of the nucleus near the nuclear pore complex?

A)the torus
B)the outer ring of the nuclear pore complex
C)the inner ring of the nuclear pore complex
D)cytoplasmic filaments that extend from the outer ring of the nuclear pore complex
E)the transporter

Question 34

A stretch of repeated sequences at the tip of a DNA molecule forming a cap at the end of the chromosome is called a ________.

A)telomere
B)chromomere
C)centromere
D)telophase
E)karyomere

Question 35

What happens if histone H1 is selectively extracted from compacted chromatin?

A)chromatin uncoils to form a more extended beaded filament
B)chromatin uncoils to form a less extended cylindrical filament
C)chromatin completely disassembles to its component nucleotides
D)chromatin breaks into small fragments
E)chromatin breaks into large fragments

Question 36

Scientists can stain chromosomes from mitotic cells and photograph the chromosomes using a microscope. Each chromosome can then be cut out of the photograph, the chromosomes matched up in homologous pairs and placed in order of decreasing size. This methodcan be used to screen individuals for chromosomal abnormalities, like extra, missing or grossly altered chromosomes. What is such a picture called?

A)karyoplan
B)eukaryote
C)karyotype
D)karyokinesis
E)prokaryote

Question 37

The fact that chromosomes should become shorter and shorter with each round of cell division is referred to as the ________.

A)shortening contradiction
B)the replication paradox
C)the short end hypothesis
D)the truncated end problem
E)the end-replication problem

Question 38

If cells cannot replicate the ends of their DNA, what should happen with each round of cell division?

A)The chromosomes should stay exactly the same length.
B)The chromosomes should get longer.
C)The mitotic spindle should shrink.
D)The chromosomes should get shorter.
E)The chromosomes should denature.

Question 39

What is the advantage of the highly condensed state of the DNA of mitotic chromosomes?

A)This state allows gene expression needed during mitosis.
B)The highly condensed state favors delivery of an intact package of DNA to each daughter cell.
C)The condensed state allows chromosomes to fuse more easily.
D)The condensed state allows replication to occur more rapidly as the cell enters mitosis.
E)The condensed state favors DNA repair prior to mitosis.

Question 40

There are genes on the X chromosome that manage to escape inactivation. What particular genes are included in this group and what might be the reason that they remain activated?

A)genes that are missing from the X chromosome; so they will be expressed equally in both sexes
B)genes that are also present on the Y chromosome; so they will be expressed equally in both sexes
C)genes that are also found on Chromosome 1; so they will be expressed equally in both sexes
D)centromere genes; so that all cells will be able to attach to the spindle
E)centromere genes; so they will be expressed equally in both sexes

Question 41

Which of the following is NOT a transcription factor identified as important for maintaining pluripotency in embryonic stem (ES)cells?

A)Oct4
B)Myc
C)Cal5
D)Sox2
E)Klf4

Question 42

Which level of control of gene expression is defined as determining if a particular gene can give rise to mRNA and, if so, how often?

A)transcriptional-level controls
B)processing-level controls
C)translational-level controls
D)replication-level controls
E)post-translational-level controls

Question 43

When present, the TATA, CAAT and GC boxes are typically found within 100 - 150 bp upstream from the transcription start site. Due to their closeness to the start of gene, they are often called ______.

A)distal promoter elements
B)proximal promoter elements
C)central promoter sites
D)primary promoter elements
E)primary promoter sites

Question 44

What strategy in transcription factor research allows the simultaneous monitoring of all sites in the genome that carry out a particular activity with the goal of identifying all of the sites bound by a given transcription factor under a given set of physiological conditions?

A)deletion mapping
B)DNA footprinting
C)genome-wide location analysis
D)FISH
E)scanning electron microscopy

Question 45

You attempt deletion mapping of a part of the promoter region of a particular gene. \ You remove a short sequence of nucleotides. Once the altered DNA is transfected into cells, the cells are able to transcribe the transfected DNA in a normal fashion. What do you conclude?

A)The sequence that was removed is an essential part of the promoter.
B)The sequence that was deleted is an important determinant of the ability to transcribe the gene.
C)The sequence that was removed is not an essential part of the promoter.
D)The deleted sequence has a moderate level of importance in promoting transcription.
E)The deleted sequence binds tightly to RNA polymerase.

Question 46

What phenomenon greatly expands the diversity of regulatory factors that can be generated from a limited number of polypeptides?

A)heterodimerization
B)homodimerization
C)heterohomodimerization
D)recombination
E)heterotrimerization

Question 47

The extent to which a given gene is transcribed presumably depends upon __________.

A)the single transcription factor bound to its upstream regulatory elements
B)the particular combination of transcription factors bound to its upstream regulatory elements
C)the particular combination of transcription factors bound to its downstream regulatory elements
D)the combination of initiation factors bound to its upstream regulatory elements
E)the combination of translational factors bound to its upstream regulatory elements

Question 48

The basic amino acid stretch in bZIP proteins _______.

A)facilitates dimerization
B)allows the protein to recognize a specific nucleotide sequence in DNA
C)prevents dimerization
D)allows the protein to recognize a specific nucleotide sequence in RNA
E)facilitates tetramerization

Question 49

The combination of a basic stretch of amino acids and a leucine zipper is known as a(n)_____ motif.

A)bHLH
B)bZIP
C)acidic zipper
D)basic zipper
E)basido zipper

Question 50

What level of control of gene expression is defined as regulating whether or not a particular mRNA is actually used in protein synthesis and, if so, how long and for how long a period of time?

A)transcriptional-level controls
B)processing-level controls
C)translational-level controls
D)replication-level controls
E)post-translational-level controls

Question 51

The success of cloning experiments led to all of the following conclusions EXCEPT:

A)the transcriptional state of a differentiated cell is reversible
B)the transcriptional state chromatin in a differentiated cell is irreversible
C)the transcriptional state chromatin in a differentiated cell is reversible
D)a nucleus from a differentiated cell can be reprogrammed by factors residing in the cytoplasm of its new environment

Question 52

What domain of a transcription factor is responsible for recognizing and associating with specific DNA base pair sequences?

A)the DNA-binding domain
B)the activation domain
C)the repression domain
D)the DNA-unwinding domain
E)the DNA-derepression domain

Question 53

Which of the following is NOT a general description of one of the gene expression regulation mechanisms that operate in eukaryotic organisms?

A)transcriptional-level controls
B)processing-level controls
C)translational-level controls
D)replication-level controls
E)post-translational-level controls

Question 54

Which transcription factor helps to activate genes needed for cell division?

A)Egr
B)Csn
C)GATA
D)trp

Question 55

You are interpreting data on a DNA chip or microarray. You expose the chip to a mixture of two cDNA populations: one from cells that were not treated with a glucocorticoid hormone (untreated controls; labeled with a red fluorescent dye)and a population from cells that were treated with glucocorticoid hormones (glucocorticoid-treated; labeled with green fluorescent dye). You look at a spot on the chip representing the gene for phosphoenolase, a gene that is turned off by glucocorticoid treatment, but is expressed in control, untreated cells. What color should the spot representing the phosphoenolase gene be?

A)red
B)green
C)yellow
D)no color, the spot is not labeled
E)brown

Question 56

The α-helical portions of the bZIP proteins ______.

A)facilitate dimerization
B)allow the protein to recognize a specific nucleotide sequence in DNA
C)prevent dimerization
D)allow the protein to recognize a specific nucleotide sequence in RNA
E)facilitate tetramerization

Question 57

You are interpreting data on a DNA chip or microarray. You expose the chip to a mixture of two cDNA populations: one from cells that were not treated with a glucocorticoid hormone (untreated controls; labeled with a red fluorescent dye)and a population from cells that were treated with glucocorticoid hormones (glucocorticoid-treated; labeled with green fluorescent dye). You look at a spot on the chip representing the gene for phosphofructokinase, a gene that is not affected by glucocorticoid treatment, but is instead expressed in all cells. What color should the spot representing the phosphofructokinase gene be?

A)red
B)green
C)yellow
D)no color, the spot is not labeled
E)brown

Question 58

Each transcription factor usually has at least two domains that mediate different aspects of their function. What are they?

A)the DNA-binding domain and the activation domain
B)the activation domain and the repression domain
C)the DNA-binding domain and the repression domain
D)the RNA-binding domain and the activation domain
E)the RNA-binding domain and the repression domain

Question 59

The helix-loop-helix (HLH)motif is often preceded by a stretch of highly ______ amino acids whose ______ charged side chains contact DNA and determine the transcription factor's sequence specificity.

A)basic, positively
B)basic, negatively
C)acidic, negatively
D)acidic, positively
E)hydrophobic, neutral

Question 60

Which type of molecule binds at the core promoter sites in association with RNA polymerase?

A)general transcription factors
B)sequence-specific transcription factors
C)elongation factors
D)initiation factors
E)termination factors

Question 61

What extends from the methylguanosine cap at the start of an mRNA to the AUG initiation codon?

A)the first intron
B)the last exon
C)the 5' UTR
D)the 3' UTR
E)the last intron

Question 62

Which genetic phenomenon below involves the conversion of specific nucleotides to other nucleotides after RNA has been transcribed?

A)translational frameshifting
B)termination codon readthrough
C)mRNA editing
D)alternative translation initiation
E)translational bypassing

Question 63

In mRNA editing, to which nitrogenous bases is adenine converted by the enzymatic removal of an amino group?

A)cytosine
B)inosine
C)guanine
D)thymine
E)uracil

Question 64

The enzymes that remove acetyl groups from histones in the chromatin are ________.

A)histone acetyltransferases
B)histone deacetylases
C)histone acetylases
D)histone methylases
E)methylacetyltransferases

Question 65

Why might localizing mRNAs in the oocyte be more efficient than localizing the proteins they encode?

A)Each mRNA can be translated into a limited number of proteins.
B)Each mRNA can be translated into a large number of proteins.
C)Messenger RNAs are easier to immobilize than proteins.
D)Localizing proteins would denature them.

Question 66

Treatment of fragmented DNA with a particular transcription factor attached at a number of sites with antibodies against that transcription factor can permit _________.

A)precipitation of DNA fragments bound to that transcription factor
B)solubilization of DNA fragments bound to that transcription factor
C)hydrolysis of DNA fragments bound to that transcription factor
D)hydrolysis of DNA fragments that remain unbound by that transcription factor
E)precipitation of DNA fragments not bound to that transcription factor

Question 67

A plant breeder is looking to create a novel bloom type highlighting the intricate colors found in the carpals of a particular lily by reducing the stamens. He is not concerned about plant fertility. What would be his most efficient way to produce new candidate plants?

A)mutate Gene A
B)mutate Gene B
C)mutate Gene C
D)mutate Gene A and B
E)mutate Gene B and C

Question 68

Transcription factors bound at the enhancer stimulate the initiation of transcription at the core promoter through the action of intermediaries called _____.

A)corepressors
B)cotranscriptors
C)coactivators
D)preinitiators
E)costimulators

Question 69

The oskar protein is required for the ________, which develop at the _______ end of the Drosophila larva.

A)formation of germ cells, anterior
B)formation of germ cells, posterior
C)formation of muscle cells, anterior
D)formation of osteocytes, posterior
E)formation of brain cells, anterior

Question 70

_______ mRNAs are preferentially localized at the anterior end of a fruit fly oocyte; ______ mRNAs are preferentially localized at the opposite or posterior end of the oocyte.

A)Bicoid, oskar
B)Oskar, bicoid
C)Bicoid, staufen
D)Staufen, bicoid
E)Oskar, staufen

Question 71

In gene expression profiling by microarray analysis, ____ sequences produced from mRNA are hybridized with ____ sequences that have been spotted onto a glass slide.

A)cDNA, complementary RNA
B)cDNA, complementary DNA
C)RNA, complementary
D)intron, exon
E)short, long

Question 72

When an adenine (A)is converted to an inosine (I), how is it subsequently read by the translational machinery?

A)It is read as a guanine (G).
B)It is read as a cytosine (C).
C)It is read as a uracil (U).
D)It is read as a thymine (T).

Question 73

The ChIP technique designed to detect genome-wide histone modifications has been developed to detect histone modifications in all of the following EXCEPT:

A)H3K9
B)H4K16
C)H3K4
D)H3K36
E)H4K15

Question 74

If an exon excised, what other RNA sequences will it be excised with it?

A)the flanking exons
B)the flanking introns
C)one flanking exon and one flanking intron
D)the promoter
E)the poly(A)sequence

Question 75

Messenger RNA editing is an example of gene expression at the _________ level.

A)transcriptional
B)translational
C)posttranslational
D)posttranscriptional
E)pretranscriptional

Question 76

Which is NOT an effect mRNA editing may have on a newly transcribed mRNA?

A)It can create new splice sites.
B)It can generate new start codons.
C)It can generate stop codons.
D)It can lead to amino acid substitutions.

Question 77

How do the proteins involved in controlling transcription of genes related to flower development associate with one another?

A)in homodimeric complexes of proteins sharing a common MADS domain
B)in heterotetrameric complexes of proteins sharing a common MADS domain
C)in heterotetrameric complexes of proteins sharing a common MARS domain
D)in homotrimeric complexes of proteins sharing a common MARS domain

Question 78

What extends from the termination codon at the end of an mRNA coding region to the end of the poly(A)tail?

A)the first intron
B)the last exon
C)the 5' UTR
D)the 3' UTR
E)the last intron

Question 79

When DNA-binding proteins are removed from immunoprecipitated DNA sequences and the DNA fragments precipitated by the antibody are subsequently sequenced directly to determine the genomic sites bound, the technique is called __________.

A)Hip-chip
B)ChIP-chip
C)ChIP-seq
D)chromatin immunoprecipitation
E)ChIP

Question 80

Evidence suggests that ________ of __________ groups from nucleosomes in the wake of an elongating RNA polymerase prevents inappropriate __________ within the internal coding region of a gene.

A)addition, acetyl, initiation of transcription
B)removal, acetyl, initiation of translation
C)removal, acetyl, initiation of transcription
D)removal, methyl, initiation of transcription
E)addition, methyl, initiation of translation