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MHT CET Medical202622 April 2026Evening ShiftBiologyMolecular Basis of InheritanceActual

Given below are two statements regarding Lac operon. Statement (I): In Lac operon, in the absence of lactose, repressor protein binds to the operator gene and represses the process. Statement (II): The lactose acts as an inducer of its own break down. In light of the above statements, choose the most appropriate answer from the options given below.

Options

  1. ABoth Statement (I) and Statement (II) are correct.
  2. BBoth Statement (I) and Statement (II) are incorrect.
  3. CStatement (I) is correct but Statement (II) is incorrect.
  4. DStatement (I) is incorrect but Statement (II) is correct.

Correct answer

A. Both Statement (I) and Statement (II) are correct.

Step-by-step solution

In the Lac operon, the i gene continuously synthesizes the repressor protein. In the absence of lactose, this repressor protein binds to the operator region, preventing RNA polymerase from transcribing the structural genes. Thus, Statement (I) is correct. When lactose is present, it acts as an inducer by binding to the repressor protein and inactivating it. This allows the transcription of genes whose products (such as -galactosidase) are responsible for the breakdown of lactose. Therefore, lactose induces the synt

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