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NEET2026ZoologyMolecular Basis of InheritanceActual

In the lac operon, the z gene codes for :

Options

  1. Apermease
  2. Btransacetylase
  3. Cbeta-galactosidase
  4. Dthe repressor of lac operon

Correct answer

C. beta-galactosidase

Step-by-step solution

In the lac operon, the structural genes are z, y, and a. The z gene codes for beta-galactosidase, which is primarily responsible for the hydrolysis of the disaccharide lactose into its monomeric units, galactose and glucose. The y gene codes for permease, which increases permeability of the cell to beta-galactosides. The a gene codes for a transacetylase. The i gene codes for the repressor of the lac operon. Answer: beta-galactosidase

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