Question 1

At any given time, most of the genes in the genome of an organism are actively undergoing gene expression.

Accepted Answer

A) True 
 B)False

Question 2

A change in an organism's environment generally results in a change in ________ ________, leading to the production of different types of proteins.

Accepted Answer

The answer of A change in an organism's environment generally...

Question 3

A cell has a repressor protein for substance A. If substance A is present in sufficient quantities,

Accepted Answer

A)   the repressor protein will be bound to RNA polymerase.
B)   the repressor protein will be bound to substance A.
C)   substance A will be bound to the operator.
D)   a repressor protein-substance A complex will be bound to RNA polymerase.

Question 4

The DNA sequences of human beings and chimpanzees are approximately 99 percent alike. What might explain the seemingly large differences that exist between these two closely related organisms?

Accepted Answer

A)   Chimpanzees use RNA as the heritable genetic material, so DNA sequences are not important.
B)   Chimpanzee DNA does not have the introns found in human DNA.
C)   Humans are eukaryotic and chimpanzees are prokaryotic.
D)   Different patterns of gene expression regulate the two organisms' genomes.

Question 5

Noncoding DNA

Accepted Answer

A)   codes for RNA but not proteins.
B)   codes for introns and spacer DNA.
C)   includes spacer DNA and transposons.
D)   includes spacer DNA and introns.

Question 6

Once a gene has been translated, no further regulation of gene expression is possible.

Accepted Answer

A) True 
 B)False  False

Question 7

The amount of DNA in a prokaryotic cell is _______ than the amount of DNA in a eukaryotic cell.

Accepted Answer

The answer of The amount of DNA in a prokaryotic...

Question 8

Which is not a way that cells can control gene expression?

Accepted Answer

A)   Tightly packed DNA is not expressed.
B)   Cells break down DNA that codes for unexpressed proteins.
C)   Cells regulate the breakdown of mRNA.
D)   Cells can inhibit translation.

Question 9

Why is regulating transcription the main way the cells control gene expression?

Accepted Answer

Transcription is the first ste...

Question 10

In this figure, are the genes that encode the enzymes needed to make tryptophan on or off?

Accepted Answer

A)   The genes are on because the genes involved in tryptophan production are housekeeping genes
B)   The genes are on because the complex of tryptophan and repressor protein allow RNA polymerase to bind to the promoter.
C)   The genes are off because the complex of tryptophan and repressor protein prevent RNA polymerase from interacting with regulatory DNA.
D)   The genes are off because when tryptophan is plentiful in the environment, RNA polymerase is not made.

Question 11

The benefit of putting a group of related genes under the control of a single _____________ is that the activation of this single regulatory sequence can lead to the production of all the proteins needed to respond to an environmental change.

Accepted Answer

The answer of The benefit of putting a group of...

Question 12

Which of the following are removed from mRNA after transcription?

Accepted Answer

A)   introns
B)   transposons
C)   spacer DNA
D)   exons

Question 13

An operator is a sequence of DNA whose function it is to

Accepted Answer

A)   bind to the chromosome to prevent replication.
B)   bind to the chromosome to prevent gene expression.
C)   control the transcription of a gene or group of genes.
D)   control the translation of a gene or group of genes.

Question 14

In E. coli when tryptophan is present in the environment,

Accepted Answer

A)   the tryptophan operator will break down tryptophan.
B)   the tryptophan-repressor protein will be unable to bind to the tryptophan operator.
C)   tryptophan will bind to a repressor protein.
D)   the tryptophan-repressor protein will be unable to bind to tryptophan. C

Question 15

Why do organisms have the ability to change gene expression?

Accepted Answer

A)   Being able to change gene expression prevents an organism from wasting energy and resources on protein production.
B)   The environment is constantly changing and an organism must be able to react to that change.
C)   Changing gene expression ensures that exactly the right proteins are available when they are needed.
D)   all of the above D

Question 16

This table shows which of these four genes are on or off in three different cell types. 
Why is the expression of the rRNA gene so different from the expression of the other genes in the table?

Accepted Answer

A)   rRNA is required for the proper functioning of all cells, but the products of the other genes are only essential to the function of one cell type.
B)   rRNA is easier to produce than the products of the other genes.
C)   The rRNA gene is found in the genomes of all three cell types, but the other genes are only found in the genomes of their specific cell type.
D)   rRNA is needed at all stages of the cell cycle, but the products of the other genes are only needed during cell division.

Question 17

Organisms control when, where, and how much of each gene product is made.

Accepted Answer

A) True 
 B)False

Question 18

In interphase, each chromosome in a cell consists of

Accepted Answer

A)   four DNA molecules.
B)   a paired DNA/RNA molecule.
C)   one DNA molecule.
D)   an RNA/enzyme complex.

Question 19

Which of the following statements is not true of eukaryotic DNA?

Accepted Answer

A)   It is located in each cell's cytoplasm.
B)   It contains transposons.
C)   It has more genes than prokaryotic DNA has.
D)   It contains many noncoding sequences.

Question 20

Housekeeping genes

Accepted Answer

A)   prevent operators from expressing genes.
B)   prevent repressors from binding.
C)   are expressed by most cells in the body.
D)   break down a cell's DNA.

Exam 14: Control of Gene Expression

At any given time, most of the genes in the genome of an organism are actively undergoing gene expression.

Correct AnswerverifiedShow Answer

A change in an organism's environment generally results in a change in ________ ________, leading to the production of different types of proteins.

Correct AnswerverifiedShow Answer

A cell has a repressor protein for substance A. If substance A is present in sufficient quantities,

Correct AnswerverifiedShow Answer

The DNA sequences of human beings and chimpanzees are approximately 99 percent alike. What might explain the seemingly large differences that exist between these two closely related organisms?

Correct AnswerverifiedShow Answer

Noncoding DNA

Correct AnswerverifiedShow Answer

Once a gene has been translated, no further regulation of gene expression is possible.

Correct AnswerverifiedFalse

The amount of DNA in a prokaryotic cell is _______ than the amount of DNA in a eukaryotic cell.

Correct AnswerverifiedShow Answer

Which is not a way that cells can control gene expression?

Correct AnswerverifiedShow Answer

Why is regulating transcription the main way the cells control gene expression?

Correct AnswerverifiedTranscription is the first ste...View AnswerShow Answer

In this figure, are the genes that encode the enzymes needed to make tryptophan on or off?

Correct AnswerverifiedShow Answer

The benefit of putting a group of related genes under the control of a single _____________ is that the activation of this single regulatory sequence can lead to the production of all the proteins needed to respond to an environmental change.

Correct AnswerverifiedShow Answer

Which of the following are removed from mRNA after transcription?

Correct AnswerverifiedShow Answer

An operator is a sequence of DNA whose function it is to

Correct AnswerverifiedShow Answer

In E. coli when tryptophan is present in the environment,

Correct AnswerverifiedC

Why do organisms have the ability to change gene expression?

Correct AnswerverifiedD

This table shows which of these four genes are on or off in three different cell types. Why is the expression of the rRNA gene so different from the expression of the other genes in the table?

Correct AnswerverifiedShow Answer

Organisms control when, where, and how much of each gene product is made.

Correct AnswerverifiedShow Answer

In interphase, each chromosome in a cell consists of

Correct AnswerverifiedShow Answer

Which of the following statements is not true of eukaryotic DNA?

Correct AnswerverifiedShow Answer

Housekeeping genes

Correct AnswerverifiedShow Answer

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False

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Transcription is the first ste...
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C

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D

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