Question 1

The binding of TFIID to the promoter _______,thereby enabling the binding of other transcription factors.

Accepted Answer

A)   methylates the DNA
B)   demethylates the DNA
C)   changes the shape of the DNA
D)   produces signals that attract other transcription factors
E)   blocks the RNA polymerase binding site

Question 2

Which statement about operons is false?

Accepted Answer

A)   The structural genes in the operon are either all on or all off at a given time.
B)   They consist of a cluster of genes with a single promoter.
C)   Their DNA is transcribed into a single molecule of mRNA.
D)   They are the units of transcriptional regulation in prokaryotes.
E)   A repressible operon is turned off unless needed.

Question 3

Which level is not a potential point of regulation of gene expression?

Accepted Answer

A)   The level of transcription
B)   The level of processing mRNA
C)   The level of mRNA stability
D)   The level of translation
E)   The level of protein export

Question 4

In the absence of substance M,a hypothetical LM operon is turned off.If substance M is abundant,it can bind to the repressor,which permits the polymerase to begin transcribing the DNA.In this case,LM is a(n) _______ operon and M acts as a(n) _______.

Accepted Answer

A)   repressible;inducer
B)   repressible;transcription factor
C)   inducible;inducer
D)   inducible;corepressor
E)   inducible;transcription factor

Question 5

In eukaryotic cells,promoters are

Accepted Answer

A)   transcribed.
B)   transcribed and translated.
C)   sequences of RNA that are spliced out.
D)   transcribed and then removed.
E)   neither transcribed nor translated.

Question 6

In which of these pairs do the two entities act in opposite ways?

Accepted Answer

A)   A constitutive gene and an activator
B)   A transcription factor and a constitutive gene
C)   A repressor and an activator
D)   A promoter and a repressor
E)   A promoter and an activator

Question 7

What is a likely advantage of transcriptional regulation over allosteric regulation?

Accepted Answer

A)   In transcriptional regulation,only the final product is regulated;thus,it is more efficient.
B)   In allosteric regulation,the continued production of enzymes is energetically costly.In transcriptional regulation,it is possible to shut down the production of the enzymes.
C)   Allosteric regulation is necessarily slower than transcriptional regulation.
D)   Allosteric regulation requires cofactors that are not required by transcriptional regulation.
E)   Transcriptional regulation can be inducible or repressible.

Question 8

What kind of mutation would lead to an increase in the expression (or inappropriate expression) of a gene?

Accepted Answer

A)   A mutation that lowers the efficiency of a repressor of the gene
B)   A mutation that lowers the efficiency of an activator of the gene
C)   A mutation that increases the efficiency of a repressor of the gene
D)   A mutation that mutates an activator for the gene such that promoter recognition decreases
E)   A mutation that mutates a repressor for the gene such that promoter recognition increases

Question 9

Which statement about viruses is true?

Accepted Answer

A)   They are not cells.
B)   They can regulate the movements of substances into and out of the cell.
C)   They can reproduce outside living cells.
D)   They are large and therefore easy to study.
E)   They are the smallest life form.

Question 10

The HIV virus that causes AIDS is a(n)

Accepted Answer

A)   arbovirus.
B)   double-stranded DNA virus.
C)   single-stranded DNA virus.
D)   porcine virus.
E)   retrovirus.

Question 11

In comparison with genes in bacterial operons,genes that encode for stress responses in plants

Accepted Answer

A)   are located closer together on the chromosome.
B)   do not alter their expression levels due to transcription factor binding.
C)   are not coordinately regulated.
D)   are located farther apart on the chromosome.
E)   do not respond to changes in environmental conditions.

Question 12

A normal E.coli cell that is grown for several hours in the presence of glucose alone will show _______ levels of the protein  β\betaβ -galactoside permease.A normal E.coli cell grown for several hours in the presence of lactase alone will show _______ levels of the protein  β\betaβ -galactoside permease.

Accepted Answer

A)   extremely low;high
B)   extremely low;extremely low
C)   high;extremely low
D)   high;high
E)   high;variable

Question 13

Genomic imprinting

Accepted Answer

A)   marks the parental origin of alleles.
B)   explains why euchromatin and heterochromatin are different.
C)   explains differences in the epigenomes of adult monozgotic twins.
D)   alters the DNA sequence.
E)   is not found in mammals.

Question 14

Early genes of a lytic bacteriophage are transcribed by

Accepted Answer

A)   late genes.
B)   viral RNA polymerase from earlier lytic cycles.
C)   host DNA polymerase.
D)   reverse transcriptase.
E)   host RNA polymerase.

Exam 11: Regulation of Gene Expression

In which of these pairs do the two entities act in opposite ways?

Correct Answer
verified

In comparison with genes in bacterial operons,genes that encode for stress responses in plants

Correct Answer
verified

Early genes of a lytic bacteriophage are transcribed by

Correct Answer
verified

What kind of mutation would lead to an increase in the expression (or inappropriate expression) of a gene?

Correct Answer
verified

Genomic imprinting

Correct Answer
verified

Which statement about viruses is true?

Correct Answer
verified

Which level is not a potential point of regulation of gene expression?

Correct Answer
verified

A normal E.coli cell that is grown for several hours in the presence of glucose alone will show _ levels of the protein $\beta$ -galactoside permease.A normal E.coli cell grown for several hours in the presence of lactase alone will show _ levels of the protein $\beta$ -galactoside permease.

Correct Answer
verified

Which statement about operons is false?

Correct Answer
verified

The HIV virus that causes AIDS is a(n)

Correct Answer
verified

In the absence of substance M,a hypothetical LM operon is turned off.If substance M is abundant,it can bind to the repressor,which permits the polymerase to begin transcribing the DNA.In this case,LM is a(n) _ operon and M acts as a(n) _.

Correct Answer
verified

In eukaryotic cells,promoters are

Correct Answer
verified

The binding of TFIID to the promoter _______,thereby enabling the binding of other transcription factors.

Correct Answer
verified

What is a likely advantage of transcriptional regulation over allosteric regulation?

Correct Answer
verified

Exam 11: Regulation of Gene Expression

In which of these pairs do the two entities act in opposite ways?

Correct AnswerverifiedShow Answer

In comparison with genes in bacterial operons,genes that encode for stress responses in plants

Correct AnswerverifiedShow Answer

Early genes of a lytic bacteriophage are transcribed by

Correct AnswerverifiedShow Answer

What kind of mutation would lead to an increase in the expression (or inappropriate expression) of a gene?

Correct AnswerverifiedShow Answer

Genomic imprinting

Correct AnswerverifiedShow Answer

Which statement about viruses is true?

Correct AnswerverifiedShow Answer

Which level is not a potential point of regulation of gene expression?

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

Which statement about operons is false?

Correct AnswerverifiedShow Answer

The HIV virus that causes AIDS is a(n)

Correct AnswerverifiedShow Answer

In the absence of substance M,a hypothetical LM operon is turned off.If substance M is abundant,it can bind to the repressor,which permits the polymerase to begin transcribing the DNA.In this case,LM is a(n) _______ operon and M acts as a(n) _______.

Correct AnswerverifiedShow Answer

In eukaryotic cells,promoters are

Correct AnswerverifiedShow Answer

The binding of TFIID to the promoter _______,thereby enabling the binding of other transcription factors.

Correct AnswerverifiedShow Answer

What is a likely advantage of transcriptional regulation over allosteric regulation?

Correct AnswerverifiedShow Answer

Correct Answer
verified

Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
verified

In the absence of substance M,a hypothetical LM operon is turned off.If substance M is abundant,it can bind to the repressor,which permits the polymerase to begin transcribing the DNA.In this case,LM is a(n) _ operon and M acts as a(n) _.

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified