Deck 28: Regulation of Gene Expression

Question 1

Matching
Choose the correct answer from the list. Not all the answers will be used.
The ______ proteins can undergo posttranslational modification by acetylation, phosphorylation, methylation, and ubiquitination.

A)globin
B)M phase
C)G₀ phase
D)necrosis
E)euchromatin
F)S phase
G)riboswitch
H)histone
I)insulators
J)heterochromatin
K)Mediator
L)1,6-allolactose
M)apoptosis
N)orphan
O)galactose

Answer 1

histone

Question 2

An organism's metabolic complexity and morphology are not always consistent with the amount of its genetic material.This inconsistency is called

A)genomic degeneracy.
B)the C-value paradox.
C)nucleotide polymorphism.
D)chromatin reorganization.
E)Prader-Willi syndrome.

Answer 2

the C-value paradox.

Question 3

A database of _____ is being compiled to examine possible genetic links to the susceptibility to disease or infection..

A)CpG islands
B)ORFs
C)SNPs
D)LINEs
E)SINEs

Answer 3

SNPs

Question 4

Matching
Choose the correct answer from the list. Not all the answers will be used.
DNA is synthesized during ______ of the cell cycle.

A)globin
B)M phase
C)G₀ phase
D)necrosis
E)euchromatin
F)S phase
G)riboswitch
H)histone
I)insulators
J)heterochromatin
K)Mediator
L)1,6-allolactose
M)apoptosis
N)orphan
O)galactose

Question 5

Matching
Choose the correct answer from the list. Not all the answers will be used.
Genes without a known function are called ______ genes.

A)globin
B)M phase
C)G₀ phase
D)necrosis
E)euchromatin
F)S phase
G)riboswitch
H)histone
I)insulators
J)heterochromatin
K)Mediator
L)1,6-allolactose
M)apoptosis
N)orphan
O)galactose

Question 6

Matching
Choose the correct answer from the list. Not all the answers will be used.
Mitosis and cell division take place during ______ of the cell cycle.

A)globin
B)M phase
C)G₀ phase
D)necrosis
E)euchromatin
F)S phase
G)riboswitch
H)histone
I)insulators
J)heterochromatin
K)Mediator
L)1,6-allolactose
M)apoptosis
N)orphan
O)galactose

Question 7

Matching
Choose the correct answer from the list. Not all the answers will be used.
To induce expression of the lac operon, _______ can be added to the cell medium.

A)globin
B)M phase
C)G₀ phase
D)necrosis
E)euchromatin
F)S phase
G)riboswitch
H)histone
I)insulators
J)heterochromatin
K)Mediator
L)1,6-allolactose
M)apoptosis
N)orphan
O)galactose

Question 8

RNA interference is a mechanism of posttranscriptional RNA-dependent

A)chromatin-remodeling.
B)gene silencing.
C)histone methylation.
D)coactivation.
E)apoptosis.

Question 9

Matching
Choose the correct answer from the list. Not all the answers will be used.
In bacteria, riboflavin can inhibit its own synthesis by binding to an mRNA element termed a ______.

A)globin
B)M phase
C)G₀ phase
D)necrosis
E)euchromatin
F)S phase
G)riboswitch
H)histone
I)insulators
J)heterochromatin
K)Mediator
L)1,6-allolactose
M)apoptosis
N)orphan
O)galactose

Question 10

Gene regulation by the JAK-STAT pathway relays signals initiated by

A)phosphorylated cytokines binding to hormone response elements.
B)steroids binding to steroid receptors inducing phosphorylation of tyrosine.
C)methylation of the SH2 domain.
D)bromodomain recruitment of coactivators.
E)ligand binding induced dimerization of cytokine receptor.

Question 11

Which of the following relates to the observation that males and females make approximately equal amounts of X-chromosome gene products?

A)the phenomenon is known as dosage compensation
B)inactivation of one of the X-chromosomes
C)unequal distribution of X-chromosome genes.
D)A and B
E)B and C

Question 12

Matching
Choose the correct answer from the list. Not all the answers will be used.
Enhancer activity can be blocked by the presence of sequences called _____.

A)globin
B)M phase
C)G₀ phase
D)necrosis
E)euchromatin
F)S phase
G)riboswitch
H)histone
I)insulators
J)heterochromatin
K)Mediator
L)1,6-allolactose
M)apoptosis
N)orphan
O)galactose

Question 13

In humans, approximately ______ of the genome encodes proteins.

A)0.4%
B)1.4%
C)14%
D)24%
E)44%

Question 14

Matching
Choose the correct answer from the list. Not all the answers will be used.
Transcriptionally active DNA in eukaryotes is called ______.

A)globin
B)M phase
C)G₀ phase
D)necrosis
E)euchromatin
F)S phase
G)riboswitch
H)histone
I)insulators
J)heterochromatin
K)Mediator
L)1,6-allolactose
M)apoptosis
N)orphan
O)galactose

Question 15

In eukaryotic cells, methylated bases are present in palindromic ______, which are often found in upstream promoter regions.

A)CpG islands
B)ORFs
C)SNPs
D)LINEs
E)SINEs

Question 16

The apparent correlation between histone modification and control over gene expression is termed

A)architectural model.
B)polymorphism.
C)chromatin remodeling.
D)the histone code.
E)acetylation.

Question 17

Matching
Choose the correct answer from the list. Not all the answers will be used.
Cell death caused by trauma is called ______.

A)globin
B)M phase
C)G₀ phase
D)necrosis
E)euchromatin
F)S phase
G)riboswitch
H)histone
I)insulators
J)heterochromatin
K)Mediator
L)1,6-allolactose
M)apoptosis
N)orphan
O)galactose

Question 18

Matching
Choose the correct answer from the list. Not all the answers will be used.
RNAP II holoenzyme contains RNAP II and the protein complex called ______.

A)globin
B)M phase
C)G₀ phase
D)necrosis
E)euchromatin
F)S phase
G)riboswitch
H)histone
I)insulators
J)heterochromatin
K)Mediator
L)1,6-allolactose
M)apoptosis
N)orphan
O)galactose

Question 19

Which of the following statements about repetitive DNA sequences is FALSE?

A)Both centromeres and telomeres contain repetitive DNA sequences.
B)Short tandem repeats, such as (CA)?_n, may be due to replication slippage.
C)Large sections of repetitive sequences are observed in prokaryotic and eukaryotic cells.
D)Familial relationships can be determined by analysis of repetitive DNA.
E)Repetitive sequences are found in some protein-coding genes.

Question 20

"Programmed" cell death is called

A)imprinting.
B)silencing.
C)necrosis.
D)coactivation.
E)apoptosis.

Question 21

How do steroid hormones influence gene expression?

A)They bind cell surface receptors which influence the concentration of second messengers.
B)They migrate between the cytosol and nucleus binding the hormone response elements to affect transcription.
C)They bind to histones, influencing their ability to form nucleosomes.
D)They bind to histones, influencing their ability to be methylated.
E)None of the above.

Question 22

How does the transcriptional machinery gain access to the nucleosome-sequestered DNA?
I.Methylation of DNA prevents histone binding.
II.Chromatin-remodeling complexes allow sections of DNA to be transiently exposed to transcription factors.
III.The transcription proteins have higher affinity for DNA and push the histones away from binding sites.

A)I, II, III
B)I, II
C)II, III
D)I, III
E)II only

Question 23

Euchromatin is

A)DNA that is tightly condensed and transcriptionally active.
B)DNA that is tightly condensed and transcriptionally inactive.
C)DNA that is not condensed and transcriptionally active.
D)DNA that is not condensed and transcriptionally inactive.
E)DNA that is not condensed, but may or may not be transcriptionally active.

Question 24

Upstream transcription factors typically contain the following domain(s)
I.a DNA binding domain.
II.an activation domain, which often is rich in negative charges.
III.an ATP binding domain, which is used to promote conformational change in the DNA.

A)I, II
B)I, II, III
C)I, II
D)II, III
E)none of the above

Question 25

Which of the following is correct regarding the function of the lac repressor protein?

A)In the presence of allolactose, the protein binds the operator inhibiting transcription.
B)In the absence of allolactose, the protein binds the operator inhibiting transcription.
C)In the presence of allolactose, the protein binds the operator enhancing transcription.
D)In the absence of allolactose, the protein binds the operator enhancing transcription.
E)None of the above.

Question 26

Eukaryotic posttranscriptional control of gene expression does NOT include

A)differential degradation of mRNA.
B)attenuation.
C)interference by RNA sequences.
D)phosphorylation of eIF2.
E)decapping of the mRNA 5 end.

Question 27

Hormone response elements
I.are DNA segments that contain repeated sequences separated by several bases.
II.bind members of the nuclear receptor superfamily of proteins.
III.are highly conserved sequences found in prokaryotic and eukaryotic cells.

A)I, II, III
B)I, II
C)II, III
D)I, III
E)II only

Question 28

HMG proteins are
I.a set of small conserved proteins containing about 50% charged amino acids.
II.regulation elements Moderated by the trp attenuation leader sequence.
III.able to alter DNA conformation by causing it to bend, unwind, and form loops.
IV.architectural proteins that regulate gene expression.

A)I, II
B)I, III
C)II, IV
D)I, III, IV
E)I, II, III

Question 29

Which stage of transcription does the lac repressor affect in order to accomplish its function?

A)initial binding of RNAP to the promoter DNA
B)initiation of transcription after RNAP has bound the promoter
C)preventing abortive initiation
D)transcription termination
E)none of the above

Question 30

How many nucleotide pairs does a bacterial genome typically contain?

A)10³ - 10⁴
B)10⁵ - 10⁶
C)10⁶ - 10⁷
D)10⁸ - 10⁹
E)none of the above

Question 31

A mutant strain of E.coli lacks a binding site for CAP at the promoter for the lac operon.How does expression of the operon compare to wild type? (The bold face row indicates units of activity observed in wild type.)

Question 32

Heterochromatin is

A)DNA that is tightly condensed and transcriptionally active.
B)DNA that is tightly condensed and transcriptionally inactive.
C)DNA that is not condensed and transcriptionally active.
D)DNA that is not condensed and transcriptionally inactive.
E)DNA that is not condensed, but may or may not be transcriptionally active.

Question 33

The p53 protein functions as a ___ arresting the cell cycle in the ___ phase.

A)cyclin; G₂
B)tumor suppressor; G₂
C)cyclin; G_o
D)tumor suppressor; G_o
E)tumor suppressor; S

Question 34

Activators and repressors bind to target DNA sites called

A)enhancers and silencers, respectively.
B)CpG islands.
C)epigenic centers.
D)all of the above
E)none of the above

Question 35

Which of the following events are necessary for efficient expression of the lac operon?
I.The lac repressor must bind inducer and dissociate from the operator site.
II.CAP must bind cAMP.
III.CAP and the repressor must simultaneously bind to RNAP.

A)I, II, III
B)I, II
C)I, III
D)II, III
E)I only

Question 36

What type of mutation causes conditions such as Huntington's disease and Fragile X syndrome?

A)an excess of trinucleotide repeats in a protein-coding gene
B)a mutation in the p53 tumor suppressor
C)a mutation in a cyclin-dependent protein kinase
D)a mutation in the retinoblastoma gene
E)a mutation in caspase-activated DNase

Question 37

Human cancers are often caused by a mutation in ___, which generally functions to restrain uncontrolled cell proliferation.

A)the cyclin gene
B)the p53 gene
C)a high mobility group (HMG)gene
D)an activator region
E)a silencer region

Question 38

Which of the following correctly describes the function of the repressor protein controlling expression of the trp operon?

A)In the presence of tryptophan, the trp repressor tryptophan complex binds the operator inhibiting transcription.
B)In the absence of tryptophan, the trp repressor tryptophan complex binds the operator inhibiting transcription.
C)In the presence of tryptophan, the trp repressor tryptophan complex binds the operator enhancing transcription.
D)In the absence of tryptophan, the trp repressor tryptophan complex binds the operator enhancing transcription.
E)None of the above.

Question 39

How many nucleotide pairs does a mammalian genome typically contain?

A)10⁵ - 10⁶
B)10⁶ - 10⁷
C)10⁸ - 10⁹
D)10⁹ - 10¹⁰
E)none of the above

Question 40

Which of the following best describes caspases?

A)They are cysteine proteases that participate in apoptosis.
B)They are cyclin-dependent protein kinases that regulate the cell cycle.
C)They are tumor suppressor DNA-binding proteins.
D)They are a class of high mobility group (HMG)proteins.
E)They are DNA repair enzymes involved in splicing immunoglobulin genes.

Question 41

Considering the E.coli trp operon, which of the following is TRUE?
I.The formation of the 2-3 hairpin is highly favored over the 1-2 hairpin when trp is low.
II.When the concentration of Trp-tRNA^Trp is low, the ribosome halts on tandem Trp codon of segment 1.
III.Formation of the 2-3 hairpin facilitates transcription and translation of the trp operon.
IV.The attenuator system has no effect when Trp levels are high.

A)I, II, III, IV
B)I, II, III
C)II, III
D)II, III, IV
E)II, IV

Question 42

On average a single nucleotide polymorphism occurs ____ in humans.

A)every 2050 base pairs
B)every 250 base pairs
C)every 1250 base pairs
D)every 2 replications
E)every 2 million base pairs

Question 43

In prokaryotes, which of the following are effective at controlling gene expression relative to the concentration of a metabolite or catabolite?
I.CAP or CRP
II.long terminal repeats (LTRs)
III.riboswitches
IV.SWI/SNF

A)I, II, III, IV
B)I, II, III
C)I, III
D)II, IV
E)III, IV

Question 44

Which of the following would likely result in the formation of RNAi?

A)injection of antisense RNA from a human into human cells
B)injection of sense RNA into C.elegans
C)injection of antisense RNA from yeast into a human
D)all of the above
E)none of the above

Question 45

Which of the following genes rarely occur in multiple copies?
I.histone proteins
II.protein-coding genes
III.gene clusters

A)I, II, III
B)I, II
C)I, III
D)II only
E)III only

Question 46

Of the human genome approximately 80% ___.

A)is made up of exonic DNA.
B)may be transcribed.
C)is made up of protein encoding genes.
D)A and C
E)A and B

Question 47

Which of the following is TRUE regarding eukaryotic mRNAs?
I.They uniformly stable.
II.The poly (A)tail appears to partially Moderate the rate of degradation.
III.The 5' cap appears to partially Moderate the rate of degradation.
IV.They have decay times ranging from 10-30 minutes.

A)I, II
B)II, III
C)II, IV
D)III, IV
E)II only

Question 48

The process of somatic recombination
I.results in antibody diversity.
II.involves selection of individual members of clustered gene sequences.
III.involves selection and recombination of specific exons on the  and/or  chain.

A)I, II, III
B)I, III
C)I, III
D)II, III
E)none of the above

Question 49

Which of the following are requirements for genetic information?
I.Information must be tapped in an orderly fashion.
II.Information must be available to direct responses in changes to internal or external conditions.
III.Information must be removable following development.

A)I, II, III
B)I, II
C)II, III
D)I, III
E)I only

Question 50

Progression through the cell cycle
I.is regulated by cyclins.
II.is controlled by Cdks.
III.is altered by CKIs.

A)I only
B)II only
C)III only
D)II , III
E)I, II, III