CAP is said to be responsible for positive regulation of the lac operon because _____.
A)CAP binds cAMP
B)CAP binds the CAP binding site
C)CAP prevents binding of the repressor to the operator
D)CAP bound to the CAP binding site increases the frequency of transcription initiation
E)extracellular glucose levels influence the ability of CAP to bind to the CAP binding site

Question

Quizplus · Accepted Answer

CAP bound to the CAP binding site increases the frequency of transcription initiation by helping RNA polymerase bind to the promoter and form a closed complex, which is necessary for transcription to occur. This positive regulation requires the presence of both CAP and cAMP.

CAP Is Said to Be Responsible for Positive Regulation of the Lac