NEETZoologyMolecular Basis of Inheritance
Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A): Regulation of the lac operon by the repressor is referred to as negative regulation. Reason (R): The repressor protein binds to the operator region of the operon and prevents RNA polymerase from transcribing the operon. In the light of the above statements, choose the most appropriate answer from t
Options
- ABoth (A) and (R) are correct and (R) is the correct explanation of (A)
- BBoth (A) and (R) are correct but (R) is not the correct explanation of (A)
- C(A) is correct but (R) is not correct
- D(A) is not correct but (R) is correct
Correct answer
A. Both (A) and (R) are correct and (R) is the correct explanation of (A)
Step-by-step solution
The regulation of the lac operon by a repressor is explicitly termed negative regulation because the regulatory protein (repressor) acts to turn off or inhibit the transcription process. The mechanism by which it achieves this inhibition is by binding to the operator region, which creates a physical blockade that prevents RNA polymerase from accessing the structural genes. Therefore, both the Assertion and Reason are correct, and the Reason correctly explains the molecular basis for why the regulation is called 'ne