Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A): If the i gene in the lac operon undergoes a mutation such that its protein product cannot bind to lactose, the operon will be permanently repressed even in a lactose-rich medium. Reason (R): The normal repressor protein is synthesised constitutively from the i gene. In the light of the above statem

Step-by-step solution

Assertion (A) is correct: The i gene codes for the repressor protein. Normally, lactose (inducer) binds to the repressor and inactivates it. If a mutation prevents the repressor from binding to lactose, the repressor will remain active and permanently bound to the operator region. This blocks RNA polymerase, keeping the operon permanently repressed regardless of the presence of lactose in the medium. Reason (R) is correct: The i gene is a constitutive gene, meaning it is transcribed continuously, and the normal rep