Question

Suppose an experimenter becomes proficient with a technique that allows her to move DNA sequences within a prokaryotic genome. If she moves the operator to the far end of the operon, past the transacetylase (lacA)gene, which of the following would likely occur when glucose levels are low?

A. The inducer will no longer bind to the repressor.

B. The lac operon genes will be transcribed continuously.

C. The repressor protein will no longer be produced.

D. The operon will never be transcribed.

E. The repressor will no longer bind to the operator.

Answer 1

Answer:

Option B

Explanation:

The lac operon genes will be transcribed continuously.

In as much as the pathway's substrate is still available and present for this operon, there would be continuously transcription of the genes. Due to yellow level of glucose, more cAMP accomplish and then RNA polymerase binds to the lac promoter effectively only when the CAP-cAMP complex is also bound.

The activity of the repressor is not present here as placing the operator to this position does not disturb its transcription.