Question

A. What is an operon?
B. Explain how a polycistronic structural gene is regulated by a common promoter and a combination of regulatory genes in a lac-operon.

Answer 1

Answer:

A _ the clusters of gene with related function are called operons

Answer 2

Operon and its structure

Explanation:

A. An operon is a section of DNA which comprises of a lot of qualities. These qualities incorporate auxiliary qualities, an administrator quality, and an administrative quality. It is a practical unit of translation and quality guideline. Operons are found in prokaryotic living beings such microscopic organisms.

B. Lac operon is composed of many three structural genes (z, y and a) which are involved in the metabolism of lactose. There are one promoter, one operator, and regulatory (i) genes.This blocks the transcription by RNA polymerase. When there is lactose, the repressor protein binds to lactose and forms allolactose which cannot bind to operator. The RNA polymerase binds to the promoter and the polycistronic mRNA is produced.