Which of the following about the Lac operon are CORRECT? (I) The lac operon in E. coli consists of a regulatory gene (lacI), a promoter, an operator, and three structural genes: lacZ ( -galactosidase), lacY (permease), lacA (transacetylase). (II) In the absence of lactose, the repressor protein binds to the operator and prevents transcription. (III) Lactose (the inducer) directly binds to the operator, displacing the

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Refer: NCERT | Class 12 | Page: 100-101 | Paragraph: 4 - 1,2 Statement (I) is correct as the lac operon consists of one regulatory gene (the i gene) and three structural genes (z, y, and a). Statement (II) is correct as the repressor protein synthesized from the i gene binds to the operator region of the operon in the absence of an inducer and prevents RNA polymerase from transcribing the operon. Statement (III) is incorrect because lactose (or allolactose) acts as an inducer by binding to the repressor protein, no