1. Tardigrade
  2. Question
  3. Biology
  4. Read the following statements for lac operon: i. Each operon has its specific operator and specific repressor. ii. The y gene codes for permease, which increases the permeability of the cell to beta-galactoside. iii. Regulation of lac operon can be visualized as regulation of enzyme synthesis by its substrate. Select the option with the correct statements.

Q. Read the following statements for lac operon:
i. Each operon has its specific operator and specific repressor.
ii. The y gene codes for permease, which increases the permeability of the cell to beta-galactoside.
iii. Regulation of lac operon can be visualized as regulation of enzyme synthesis by its substrate.
Select the option with the correct statements.

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Solution:

The lac operon is a control of gene system characterised in Escherichia coli for the regulation of the gene for the utilization of lactose. Lac operon genes Z, Y, and A represent the genes whose products are involved in digesting lactose. In the normal condition, the genes do not function because a repressor protein is active and bound to the DNA preventing transcription. When the repressor protein is bound to the DNA, RNA polymerase cannot bind to the DNA. The protein must be removed before the genes can be transcribed. The repressor protein is produced by a regulator gene. The region of DNA where the repressor protein binds is the operator site. The promoter site is a region of DNA where RNA polymerase can bind. The entire unit (promoter, operator, and genes) is an operon.