What effect does the presence of ample glucose have on the amount of lac operon transcription?
A) It increases the cAMP concentration, which in turn causes a decreased rate of transcription.
B) It decreases the cAMP concentration, which in turn causes an increased rate of transcription.
C) It increases the rate of transcription.
D) It decreases the rate of transcription.
E) None of the above

Question

Quizplus · Accepted Answer

Ample glucose leads to the production of ATP, which inhibits the activity of adenylate cyclase, the enzyme responsible for synthesizing cAMP. This results in a decrease in the concentration of cAMP, which is required for the binding of the CAP-cAMP complex to the lac operon promoter. A decrease in the concentration of the CAP-cAMP complex results in a decrease in the rate of transcription.

What Effect Does the Presence of Ample Glucose Have on the Amount