MHT CET 202624 AprilMorning Shift
- Exam
- MHT CET
- Year
- 2026
- Date
- 24 April
- Shift
- Morning Shift
- Subject
- Biology
- Chapter
- Molecular Basis of Inheritance
MHT CET 2026 · 24 April · Morning Shift · Biology · Molecular Basis of Inheritance
The repressor protein in lac operon is produced by the action of...
The repressor protein in lac operon is produced by the action of ________.
Options
- Aoperator gene
- Bregulator gene
- Cpromoter gene
- Dstructural gene
Correct answer
B. regulator gene
Step-by-step solution
The lac operon consists of regulatory and structural genes.
The regulator gene (i gene) codes for the repressor protein of the lac operon. This repressor protein binds to the operator region and prevents RNA polymerase from transcribing the structural genes.
The operator gene is the site where the repressor binds.
The promoter gene is the site where RNA polymerase binds to initiate transcription.
The structural genes (z, y, and a) code for enzymes required for lactose metabolism.
Answer: regulator gene
The regulator gene (i gene) codes for the repressor protein of the lac operon. This repressor protein binds to the operator region and prevents RNA polymerase from transcribing the structural genes.
The operator gene is the site where the repressor binds.
The promoter gene is the site where RNA polymerase binds to initiate transcription.
The structural genes (z, y, and a) code for enzymes required for lactose metabolism.
Answer: regulator gene