Question

Match the list-1 with list-2 and select the correct option:

• A. A - II, B - I, C - IV, D - III
• B. A - II, B - I, C - III, D - IV
• C. A - I, B - IV, C - II, D - III
• D. A - III, B - II, C - I, D - IV

Hint:

{Mnemonic:} {P}romoter binds {P}olymerase.

Answer 1

The Correct Option is A

Step 1: Understand the Lac Operon Components:

Operator site (A): The DNA sequence where the Repressor protein binds to prevent transcription.
Match: II.
Promoter site (B): The DNA sequence where RNA Polymerase binds to initiate transcription.
Match: I.
Regulator gene (C): The gene (e.g., \textit{lacI}) that codes for the Repressor protein.
Match: IV.
Structural gene (D): The genes (e.g., \textit{lacZ, lacY, lacA}) that code for functional proteins or enzymes (like $\beta$-galactosidase).
Match: III.

Step 2: Sequence:
A - II, B - I, C - IV, D - III. This matches Option (A).