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Question: Answered & Verified by Expert
In lac-operon, which protein is not regulated by the repressor?
BiologyMolecular Basis of InheritanceNEET
Options:
  • A Galactosidase
  • B Lactose Permease
  • C Tryptophan synthetase
  • D Transacetylase
Solution:
2894 Upvotes Verified Answer
The correct answer is: Tryptophan synthetase
Lac operon consists of three structural gene X, Y, and A. Gene X synthesizes enzyme beta-galactosidase which breaks lactose into glucose and galactose. Gene Y synthesizes enzyme Lactose permease which increases membrane permeability for lactose. Gene A synthesizes enzyme transacetylase which degrades the galactose.

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