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(a) Name the molecule 'X' synthesised by...


(a) Name the molecule 'X' synthesised by 'I' gene. How does this molecule get inactivated ?
(b) Which one of the structural genes code for `beta`-galactosidase ?
(c) When will the transcription of this gene stop?

Text Solution

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(a) Molecule 'X' synthesised by ' i' gene is repressor of the Lac operon. The repressor is inactivated by interaction with the inducer (i.e., lactose).
(b) The gene 'Z' codes for beta-galactosidase.
(c) Transcription of this gene stops as soon as the inducer is usedup i.e., in absence of inducer. Once whole of lactose is consumed and there is no inducer present to bind to the repressor, the repressor becomes active and switches off the operon.
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