The $lac$ operon is a part of which of the following?

What does the $i$ gene encode in the $lac$ operon?

Select two statements out of the four given statements $(i-iv)$ with respect to the $lac$ operon.
$(i)$ Glucose or galactose binds with the repressor and inactivates it.
$(ii)$ In the absence of lactose,the repressor binds with the operator.
$(iii)$ The $Z$-gene codes for permease.
$(iv)$ It was elucidated by Francois Jacob and Jacques Monod.

The $lac \, y$ gene codes for which of the following?

Which gene produces the lactose repressor?

An environmental agent that triggers transcription from an operon is a: