Question 1

What is the direct cause of catabolite repression?

Accepted Answer

A)   the synthesis of fi- galactosidase
B)   the presence of glucose and lactose in a growth medium
C)   binding of CAP to the DNA
D)   a cellular deficiency of cyclic AMPE) All of the above
F) A) and D)

Question 2

Explain why one cell of a pathogenic bacterium by itself typically does not secrete a toxin, despite the species as a whole being characterized as toxin producing.

Accepted Answer

One pathogenic bacterium is unlikely to ...

Question 3

Explain why regulation of enzyme synthesis is more time consuming than regulation of enzymatic activity.

Accepted Answer

Regulating enzyme synthesis requires eit...

Question 4

Heat shock proteins perform which of the following functions?

Accepted Answer

A)   prevent aggregation of newly synthesized proteins
B)   remove denatured or irreversibly aggregated proteins
C)   catalyze the correct folding of misfolded proteins
D)   all of the aboveE) B) and D)
F) None of the above

Question 5

________are RNA molecules that resemble repressors and activators in binding metabolites and regulating gene expression.

Accepted Answer

The answer of ________are RNA molecules that resemble repressors and...

Question 6

Describe the basic two- component regulatory system.

Accepted Answer

The first component of the system involv...

Question 7

Arginine in the culture medium

Accepted Answer

A)   has no effect on the enzymes required for the production of arginine.
B)   enhances the synthesis of the enzymes required for the production of arginine.
C)   neutralizes the enzymes required for the production of arginine.
D)   represses the synthesis of the enzymes required for the production of arginine.E) A) and C)
F) A) and B)

Question 8

Provide evidence that supports the hypothesis that riboswitches are remnants of the RNA world when catalytic RNAs were the only self- replicating life forms.

Accepted Answer

The answer of Provide evidence that supports the hypothesis that...

Question 9

The regulation of enzyme synthesis is usually a more rapid process than the regulation of enzyme activity.

Accepted Answer

A) True 
 B)False

Question 10

In most cases, the first product of a particular biosynthetic pathway represses the enzymes of the pathway.

Accepted Answer

A) True 
 B)False

Question 11

Cyclic AMP is synthesized from ATP by an enzyme called

Accepted Answer

A)   catabolite activator protein (CAP)  activase.
B)   RNA polymerase.
C)   adenylate cyclase.
D)   cAMP receptor protein (CRP)  receptase.E) B) and D)
F) B) and C) C

Question 12

Explain the translational attenuation mechanism.

Accepted Answer

Attenuation is a mechanism that controls...

Question 13

Which of the following is necessary for negative control of the tryptophan operon?

Accepted Answer

A)   leader sequence
B)   operator
C)   promoter
D)   all of the aboveE) B) and D)
F) B) and C) D

Question 14

Most DNA- binding proteins interact with DNA in a sequence- specific manner.

Accepted Answer

A) True 
 B)False

Question 15

Explain the sequence of events that would follow the transfer of an organism from a complex medium to a minimal medium.

Accepted Answer

Answers will vary but should include the overall need for an increased number of genes to be turned on, which were not necessary in a complex medium. For example, tRNA synthetases for amino acids would need to be made if the minimal medium did not contain sufficient quantities of each amino acid required during translation of peptides.

Question 16

The catabolism of the sugar maltose in Escherichia coli is an example of a system that involves positive regulation.

Accepted Answer

A) True 
 B)False

Question 17

Enzyme repression and induction occur at the level of

Accepted Answer

A)   translation.
B)   pretranscription.
C)   transcription.
D)   posttranslation.E) B) and D)
F) All of the above

Question 18

In the tryptophan operon, translation of the leader peptide regulates transcription of the tryptophan genes downstream and is called attenuation.

Accepted Answer

A) True 
 B)False

Question 19

In negative control of transcription, how does the presence of an inducer affect transcription?

Accepted Answer

A)   The inducer does not bind to the operator.
B)   The inducer binds to the operator.
C)   The inducer causes the repressor to bind to the operator.
D)   The inducer prevents the repressor from binding to the operator.E) All of the above
F) A) and C)

Question 20

Explain why cellular cannibalism is beneficial for sporulating Bacillus subtilis.

Accepted Answer

A cell that undergoes sporulation in res...

Exam 8: Regulation of Gene Expression

What is the direct cause of catabolite repression?

Correct Answer
verified

Explain why one cell of a pathogenic bacterium by itself typically does not secrete a toxin, despite the species as a whole being characterized as toxin producing.

Correct Answer
verified
One pathogenic bacterium is unlikely to ...
View Answer

Explain why regulation of enzyme synthesis is more time consuming than regulation of enzymatic activity.

Correct Answer
verified
Regulating enzyme synthesis requires eit...
View Answer

Heat shock proteins perform which of the following functions?

Correct Answer
verified

________are RNA molecules that resemble repressors and activators in binding metabolites and regulating gene expression.

Correct Answer
verified

Describe the basic two- component regulatory system.

Correct Answer
verified
The first component of the system involv...
View Answer

Arginine in the culture medium

Correct Answer
verified

Provide evidence that supports the hypothesis that riboswitches are remnants of the RNA world when catalytic RNAs were the only self- replicating life forms.

Correct Answer
verified

The regulation of enzyme synthesis is usually a more rapid process than the regulation of enzyme activity.

Correct Answer
verified

In most cases, the first product of a particular biosynthetic pathway represses the enzymes of the pathway.

Correct Answer
verified

Cyclic AMP is synthesized from ATP by an enzyme called

Correct Answer
verified
C

Explain the translational attenuation mechanism.

Correct Answer
verified
Attenuation is a mechanism that controls...
View Answer

Which of the following is necessary for negative control of the tryptophan operon?

Correct Answer
verified
D

Most DNA- binding proteins interact with DNA in a sequence- specific manner.

Correct Answer
verified

Explain the sequence of events that would follow the transfer of an organism from a complex medium to a minimal medium.

The catabolism of the sugar maltose in Escherichia coli is an example of a system that involves positive regulation.

Correct Answer
verified

Enzyme repression and induction occur at the level of

Correct Answer
verified

In the tryptophan operon, translation of the leader peptide regulates transcription of the tryptophan genes downstream and is called attenuation.

Correct Answer
verified

In negative control of transcription, how does the presence of an inducer affect transcription?

Correct Answer
verified

Explain why cellular cannibalism is beneficial for sporulating Bacillus subtilis.

Correct Answer
verified
A cell that undergoes sporulation in res...
View Answer

Exam 8: Regulation of Gene Expression

What is the direct cause of catabolite repression?

Correct AnswerverifiedShow Answer

Explain why one cell of a pathogenic bacterium by itself typically does not secrete a toxin, despite the species as a whole being characterized as toxin producing.

Correct AnswerverifiedOne pathogenic bacterium is unlikely to ...View AnswerShow Answer

Explain why regulation of enzyme synthesis is more time consuming than regulation of enzymatic activity.

Correct AnswerverifiedRegulating enzyme synthesis requires eit...View AnswerShow Answer

Heat shock proteins perform which of the following functions?

Correct AnswerverifiedShow Answer

________are RNA molecules that resemble repressors and activators in binding metabolites and regulating gene expression.

Correct AnswerverifiedShow Answer

Describe the basic two- component regulatory system.

Correct AnswerverifiedThe first component of the system involv...View AnswerShow Answer

Arginine in the culture medium

Correct AnswerverifiedShow Answer

Provide evidence that supports the hypothesis that riboswitches are remnants of the RNA world when catalytic RNAs were the only self- replicating life forms.

Correct AnswerverifiedShow Answer

The regulation of enzyme synthesis is usually a more rapid process than the regulation of enzyme activity.

Correct AnswerverifiedShow Answer

In most cases, the first product of a particular biosynthetic pathway represses the enzymes of the pathway.

Correct AnswerverifiedShow Answer

Cyclic AMP is synthesized from ATP by an enzyme called

Correct AnswerverifiedC

Explain the translational attenuation mechanism.

Correct AnswerverifiedAttenuation is a mechanism that controls...View AnswerShow Answer

Which of the following is necessary for negative control of the tryptophan operon?

Correct AnswerverifiedD

Most DNA- binding proteins interact with DNA in a sequence- specific manner.

Correct AnswerverifiedShow Answer

Explain the sequence of events that would follow the transfer of an organism from a complex medium to a minimal medium.

The catabolism of the sugar maltose in Escherichia coli is an example of a system that involves positive regulation.

Correct AnswerverifiedShow Answer

Enzyme repression and induction occur at the level of

Correct AnswerverifiedShow Answer

In the tryptophan operon, translation of the leader peptide regulates transcription of the tryptophan genes downstream and is called attenuation.

Correct AnswerverifiedShow Answer

In negative control of transcription, how does the presence of an inducer affect transcription?

Correct AnswerverifiedShow Answer

Explain why cellular cannibalism is beneficial for sporulating Bacillus subtilis.

Correct AnswerverifiedA cell that undergoes sporulation in res...View AnswerShow Answer

Correct Answer
verified

Correct Answer
verified
One pathogenic bacterium is unlikely to ...
View Answer

Correct Answer
verified
Regulating enzyme synthesis requires eit...
View Answer

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified
The first component of the system involv...
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Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
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C

Correct Answer
verified
Attenuation is a mechanism that controls...
View Answer

Correct Answer
verified
D

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified
A cell that undergoes sporulation in res...
View Answer