Question

The repressor protein is encoded by _________________

(a) regulatory gene

(b) structural gene

(c) transfer-DNA

(d) ribosomal-RNA

This question was posed to me in final exam.

Question is from Gene Expression Control in division Control of Gene Expression of Cell Biology

Answer 1

The correct answer is:

(a) regulatory gene

Explanation:

A regulatory gene encodes a repressor protein. The repressor protein binds to the operator region of the operon, preventing the transcription of the associated structural genes. This mechanism is part of the regulation of gene expression in prokaryotes, particularly in systems like the lac operon. The regulatory gene controls the production of the repressor, which in turn regulates the expression of other genes involved in specific metabolic processes or pathways.