(a) Name the molecule 'X' synthesised by 'i' gene. How does this molecule get inactivated?
(b) Which one of the structural genes codes for -galactosidase?
(c) When will the transcription of this gene stop?
(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 of -galactosidase.
(c) In absence of inducer or lactose the repressor protein binds to the operator region of the operon and prevents RNA polymerase from transcription of the gene.