Question

Select the two correct statements out of the four (a-d) given below about lac operon.

• A. Glucose or galactose may bind with the repressor and inactivate it
• B. In the absence of lactose the repressor binds with the operator region
• C. The z-gene codes for permease
• D. This was eluciated by Francois Jacob and Jacque Monod

Answer 1

Answer: (B), (C)

The z-gene codes for permease

In the lac operon, lactose binds with the repressor to inactivate it and leads to the transcription of the genes in the operon. The lac operon consists of three structural genes, and a promoter, a terminator, regulator, and an operator. The three structural genes are: lacZ coding for β - galactosidase, lacY β - galactosidase permease, and lacA β - galactosidase transacetylase.