1. Tardigrade
  2. Question
  3. Biology
  4. The regulator gene is denoted as i–gene in the lac operon. What does the term "i" denote?

Q. The regulator gene is denoted as i–gene in the lac operon. What does the term "i" denote?

 73  174 NTA AbhyasNTA Abhyas 2020 Report Error

Solution:

"i" here indicates inhibitor. The regulator or i-gene in lac operon synthesizes a repressor protein to regulate the functioning of the structural gene.
The repressor protein inhibits or represses the transcription of the lac operon by binding to the operator region, which overlaps the promoter region. Hence, it blocks the binding of RNA polymerase at the promoter region inhibiting the transcription of the operon.
However, the repressor protein in lac-operon gets deactivated by an inducer that is lactose.
Solution