In the prokaryotic lac operon system, a repressor remains bound to the ____ unless lactose is present.
A)operators
B)promoter
C)enhancer
D)operon
E)gene

Question

Quizplus · Accepted Answer

The operator is the DNA sequence to which the repressor protein binds. In the absence of lactose, the repressor remains bound to the operator, preventing RNA polymerase from transcribing the genes in the operon. When lactose is present, it binds to the repressor and causes a conformational change, releasing it from the operator and allowing transcription to occur.

In the Prokaryotic Lac Operon System, a Repressor Remains Bound