NEET BiologyClass 12Regulation of Gene Expression — the lac operonMediumStatement based

Consider the following statements about regulation of the lac operon in E. coli. Which one/ones is/are correct?

  • Statement I: In the absence of an inducer such as lactose, the repressor protein made by the i gene binds to the operator region and prevents RNA polymerase from transcribing the structural genes.
  • Statement II: The inducer (lactose or allolactose) switches the operon on by binding directly to the operator DNA and physically pushing the repressor off it.

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