Question

you are studying regulation of a prokaryotic operon. experiments show that expression of the operon is increased when levels of biosynthetic product from that pathway are low. based on this information, what is a likely mode of regulation? multiple choice the product binds to the biosynthetic enzymes, blocking them directly. the product binds a repressor, allowing it to bind the operator. the product binds a repressor, preventing it from binding the operator. the product binds an activator, helping rna polymerase to bind the promoter.

Explanation:

In prokaryotic operon regulation, when the biosynthetic product level is low and operon expression increases, it suggests a repressible system. In a repressible system, the product typically binds to a repressor, activating it so it can bind the operator and prevent transcription. When product levels are low, the repressor is not activated and operon expression can occur.

Answer:

The product binds a repressor, allowing it to bind the operator.