Question 1

Which of the following statements about gene regulation concerning operons is INCORRECT?

Accepted Answer

A)   A negative repressible gene is controlled by a regulatory protein that inhibits transcription.
B)   For a gene under negative repressible control, a small molecule is required to prevent the gene's repressor from binding to DNA.
C)   For a gene under positive repressible control, the normal state is transcription of a gene, stimulated by a transcriptional activator.
D)   A regulator gene has its own promoter and is transcribed into an independent mRNA.
E)   Presence of operons where genes of related functions are clustered is common in bacteria but not in eukaryotes.F) B) and E)
G) A) and E)

Question 2

Which of the following statements about DNA-binding proteins is NOT true?

Accepted Answer

A)   Specific amino acids within the motif form hydrogen bonds with DNA.
B)   These proteins can affect the expression of a gene.
C)   Most DNA-binding proteins bind dynamically.
D)   Some of these proteins incorporate a metal ion such as zinc.
E)   Once bound, most of DNA-binding proteins remain on DNA permanently.F) B) and E)
G) C) and D)

Question 3

Fill in the blanks in the following table for the transcription status of the lac operon ((+) for transcription and (-) for no transcription) in the absence or presence of lactose. The first line is filled in for reference.

Accepted Answer

The answer of Fill in the blanks in the following...

Question 4

Describe one similarity and one difference in how the trp and lac repressor proteins function.

Accepted Answer

One similarity between the trp and lac r...

Question 5

The formation of 1+2 and 3+4 secondary structures of 5' UTR region mRNA from the trp operon is triggered when:

Accepted Answer

A)   the tryptophan level inside the bacterial cell is extremely low.
B)   the tryptophan level inside the bacterial cell is high.
C)   the repressor protein fails to bind to the operator.
D)   there is a spontaneous mutation introduced into the 5' UTR.
E)   the structural gene transcription within the trp operon gets initiated.F) A) and E)
G) A) and D)

Question 6

An E. coli strain of chromosomal genotype lacI- lacP+ lacO+ lacZ+ lacY+ constitutively expresses the genes of the lac operon. The strain is converted to wild-type lac operon regulation by the addition of an extra piece of DNA. What gene or genes are contained on this extra DNA that explain this conversion to wild type? Include an explanation of cis- or trans-acting factors and how they work.

Accepted Answer

The extra piece of DNA contains the wild...

Question 7

Which of the following statements about regulation of gene expression is CORRECT?

Accepted Answer

A)   An inducible gene is transcribed when a specific substance is absent.
B)   A gene is any DNA sequence that is transcribed into an mRNA molecule only.
C)   All genes are transcribed at all times as long as they have a functional promoter.
D)   The regulation of gene expression is the same in both eukaryotes and prokaryotes.
E)   The regulation of gene expression is critical for the control of life processes in all organisms.F) A) and B)
G) All of the above

Question 8

A partial diploid E. coli cell of lacI+ lacP- lacOc lacI+ lacY+ / lacIs lacP+lacO+ lacZ+ lacY- will synthesize:

Accepted Answer

A)   both lacZ and lacY functional gene products in the absence of lactose.
B)   neither lacZ nor lacY functional gene products in the presence of lactose.
C)   both lacZ and lacY functional gene products in the presence of lactose.
D)   lacY but not a functional lacZ gene product in the absence of lactose.
E)   lacZ but not a functional lacY gene product in the absence of lactose.F) A) and D)
G) B) and E)

Exam 16: Control of Gene Expression in Prokaryotes

Which of the following statements about DNA-binding proteins is NOT true?

Correct Answer
verified

Describe one similarity and one difference in how the trp and lac repressor proteins function.

Correct Answer
Answered by ExamLex AI
One similarity between the trp and lac r...
View Answer

The formation of 1+2 and 3+4 secondary structures of 5' UTR region mRNA from the trp operon is triggered when:

Correct Answer
verified

Fill in the blanks in the following table for the transcription status of the lac operon ((+) for transcription and (-) for no transcription) in the absence or presence of lactose. The first line is filled in for reference.

Correct Answer
verified

Correct Answer
Answered by ExamLex AI
The extra piece of DNA contains the wild...
View Answer

Which of the following statements about gene regulation concerning operons is INCORRECT?

Correct Answer
verified

A partial diploid E. coli cell of lacI⁺ lacP^-lacO^c lacI⁺lacY⁺ / lacI^s lacP⁺lacO⁺ lacZ⁺ lacY^- will synthesize:

Correct Answer
verified

Which of the following statements about regulation of gene expression is CORRECT?

Correct Answer
verified

Exam 16: Control of Gene Expression in Prokaryotes

Which of the following statements about DNA-binding proteins is NOT true?

Correct AnswerverifiedShow Answer

Describe one similarity and one difference in how the trp and lac repressor proteins function.

Correct AnswerAnswered by ExamLex AIOne similarity between the trp and lac r...View AnswerShow Answer

The formation of 1+2 and 3+4 secondary structures of 5' UTR region mRNA from the trp operon is triggered when:

Correct AnswerverifiedShow Answer

Fill in the blanks in the following table for the transcription status of the lac operon ((+) for transcription and (-) for no transcription) in the absence or presence of lactose. The first line is filled in for reference.

Correct AnswerverifiedShow Answer

Correct AnswerAnswered by ExamLex AIThe extra piece of DNA contains the wild...View AnswerShow Answer

Which of the following statements about gene regulation concerning operons is INCORRECT?

Correct AnswerverifiedShow Answer

A partial diploid E. coli cell of lacI+ lacP- lacOc lacI+ lacY+ / lacIs lacP+lacO+ lacZ+ lacY- will synthesize:

Correct AnswerverifiedShow Answer

Which of the following statements about regulation of gene expression is CORRECT?

Correct AnswerverifiedShow Answer

Correct Answer
verified

Correct Answer
Answered by ExamLex AI
One similarity between the trp and lac r...
View Answer

Correct Answer
verified

Correct Answer
verified

Correct Answer
Answered by ExamLex AI
The extra piece of DNA contains the wild...
View Answer

Correct Answer
verified

A partial diploid E. coli cell of lacI⁺ lacP^-lacO^c lacI⁺lacY⁺ / lacI^s lacP⁺lacO⁺ lacZ⁺ lacY^- will synthesize:

Correct Answer
verified

Correct Answer
verified