Homework SourseBIO Cell and Molecular Bio ANSWER ALL 1 Which of the followi
BIO: Cell and Molecular Bio
ANSWER ALL
1 Which of the following describes the lac operon in E. coli when both lactose and glucose are present in the culture medium?
A) CAP, but not the lac repressor, is bound to the lac operon\'s regulatory DNA, and the lac operon is expressed.
B) CAP and the lac repressor are both bound to the lac operon\'s regulatory DNA, and the lac operon is not expressed.
C) The lac repressor, but not CAP, is bound to the lac operon\'s regulatory DNA, and the lac operon is not expressed.
D) Neither CAP nor the lac repressor is bound to the lac operon\'s regulatory DNA, and the lac operon is not expressed.
2 In the bacterial cell, the trytophan operon encodes the genes needed to synthesize tryptophan. When the concentration of typtophan inside the cell is high:
A it inactivates the tryptophan repressor which shuts down the tryptophan operon.
B it inactivates the tryptophan repressor allowing transcription of the tryptophan operon.
C it activates tytophan repressor which shuts down the tytophan operon.
3 which of the following statements is NOT true about the differences between liver cells and kidney cells in the same organism?
A They contain different sets of proteins
B they contain different genes
C they contain the same genes but express them differently
4 which is not involved in post-transcriptional control?
A riboswitch
B DNA methylation
C RNA interference
D microRNA
5 what is a riboswitch?
A a small molecule that regulates the translation of specific mRNAs
B an mRNA that can regulate its own transcription and translation
C a gene regulatory protein that turns on the expression of ribosomal proteins
BIO: Cell and Molecular Bio
ANSWER ALL
1 Which of the following describes the lac operon in E. coli when both lactose and glucose are present in the culture medium?
A) CAP, but not the lac repressor, is bound to the lac operon\'s regulatory DNA, and the lac operon is expressed.
B) CAP and the lac repressor are both bound to the lac operon\'s regulatory DNA, and the lac operon is not expressed.
C) The lac repressor, but not CAP, is bound to the lac operon\'s regulatory DNA, and the lac operon is not expressed.
D) Neither CAP nor the lac repressor is bound to the lac operon\'s regulatory DNA, and the lac operon is not expressed.
2 In the bacterial cell, the trytophan operon encodes the genes needed to synthesize tryptophan. When the concentration of typtophan inside the cell is high:
A it inactivates the tryptophan repressor which shuts down the tryptophan operon.
B it inactivates the tryptophan repressor allowing transcription of the tryptophan operon.
C it activates tytophan repressor which shuts down the tytophan operon.
3 which of the following statements is NOT true about the differences between liver cells and kidney cells in the same organism?
A They contain different sets of proteins
B they contain different genes
C they contain the same genes but express them differently
4 which is not involved in post-transcriptional control?
A riboswitch
B DNA methylation
C RNA interference
D microRNA
5 what is a riboswitch?
A a small molecule that regulates the translation of specific mRNAs
B an mRNA that can regulate its own transcription and translation
C a gene regulatory protein that turns on the expression of ribosomal proteins
BIO: Cell and Molecular Bio
ANSWER ALL
1 Which of the following describes the lac operon in E. coli when both lactose and glucose are present in the culture medium?
A) CAP, but not the lac repressor, is bound to the lac operon\'s regulatory DNA, and the lac operon is expressed.
B) CAP and the lac repressor are both bound to the lac operon\'s regulatory DNA, and the lac operon is not expressed.
C) The lac repressor, but not CAP, is bound to the lac operon\'s regulatory DNA, and the lac operon is not expressed.
D) Neither CAP nor the lac repressor is bound to the lac operon\'s regulatory DNA, and the lac operon is not expressed.
2 In the bacterial cell, the trytophan operon encodes the genes needed to synthesize tryptophan. When the concentration of typtophan inside the cell is high:
A it inactivates the tryptophan repressor which shuts down the tryptophan operon.
B it inactivates the tryptophan repressor allowing transcription of the tryptophan operon.
C it activates tytophan repressor which shuts down the tytophan operon.
3 which of the following statements is NOT true about the differences between liver cells and kidney cells in the same organism?
A They contain different sets of proteins
B they contain different genes
C they contain the same genes but express them differently
4 which is not involved in post-transcriptional control?
A riboswitch
B DNA methylation
C RNA interference
D microRNA
5 what is a riboswitch?
A a small molecule that regulates the translation of specific mRNAs
B an mRNA that can regulate its own transcription and translation
C a gene regulatory protein that turns on the expression of ribosomal proteins
Solution
1). D) Neither CAP nor the lac repressor is bound to the lac operon\'s regulatory DNA, and the lac operon is not expressed.
When both glucose and lactose are present, lac repressor does not bound to lac operator. This is because small amount of lactose enzymes are synthesized in the presence of both glucose and lactose. The cAMP is bound to the CAP protein only in the absence of glucose.
