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MODEL PAPER 1 — BIOLOGY STD 12 Science — Question

Rajasthan BoardEnglish MediumSTD 12 ScienceBIOLOGYMODEL PAPER 13 Marks
Question
Given below is a schematic representation of a lac operon. Answer the following questions:

i. Identify i and p.
ii. Name the inducer for this operon.
iii. Explain the function of inducer for this operon.
✓

Answer

i. i-Regulatory gene, p-Promoter gene.
ii. The Inducer is lactose.
iii. Functions of Lactose
a. Enters the cell and binds to the repressor and inactivates it.
b. As a result, repressor cannot bind to the operator. This allows RNA polymerase to have access to the promoter and transcription proceeds.

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