Transcription of the structural genes in an inducible operon
A) occurs continuously in the cell.
B) starts when the pathway's substrate is present.
C) starts when the pathway's product is present.
D) stops when the pathway's product is present.
E) does not result in the production of enzymes.

Question

Quizplus · Accepted Answer

Transcription of the structural genes in an inducible operon starts when the pathway's substrate is present. This is because inducible operons are normally turned off and need to be induced by specific molecules, called inducers, which are usually the substrate of the pathway. Only then can the transcription of the structural genes occur and result in the production of enzymes.

Transcription of the Structural Genes in an Inducible Operon