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MODEL PAPER 6 — BIOLOGY STD 12 Science — Question

Rajasthan BoardEnglish MediumSTD 12 ScienceBIOLOGYMODEL PAPER 62 Marks
Question
Study the figure given and answer the questions.
Image
i. How does the repressor molecule get inactivated?
ii. When does the transcription of lac mRNA stop?
iii. Name the enzyme transcribed by the gene z.
✓

Answer

i. When an inducer, e.g., lactose binds to the repressor, the repressor is inactivated.
ii. The transcription of lac mRNA stops when lactose becomes exhausted or when there is no need for energy to the cells.
iii. β-galactosidase.

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