NEETZoologyMolecular Basis of Inheritance
Match List-I with List-II regarding the components of the lac operon. List-I List-II (A) Promoter (I) Codes for the repressor protein (B) Operator (II) Binding site for the repressor protein (C) i gene (III) Inactivates the repressor protein (D) Inducer (IV) Binding site for RNA polymerase Choose the correct answer from the options given below:
Options
- A(A)-(II), (B)-(IV), (C)-(I), (D)-(III)
- B(A)-(IV), (B)-(I), (C)-(II), (D)-(III)
- C(A)-(IV), (B)-(II), (C)-(I), (D)-(III)
- D(A)-(II), (B)-(III), (C)-(I), (D)-(IV)
Correct answer
C. (A)-(IV), (B)-(II), (C)-(I), (D)-(III)
Step-by-step solution
In the lac operon, the promoter is the specific DNA sequence where RNA polymerase binds to initiate transcription (A matches IV). The operator is the region adjacent to the promoter where the active repressor protein binds to block transcription (B matches II). The i gene is the regulatory gene that codes for the repressor protein (C matches I). The inducer (such as lactose or allolactose) binds to the repressor protein, inactivating it and preventing it from binding to the operator, thereby allowing transcription