The regulatory genes that encode for the repressor protein are always being transcribed; it is the presence or absence of the lactose molecule that controls whether the operon is on or off. a) true
b) false

The answer is A.

Explanation:

The lac repressor protein can prevent or let the transcription and production of the operan. When there is lactose not present in the body, the lac repressor protein prevents the production of the operan by RNA polymerase but when lactose is present, it let's the operan to get produced . So the answer is yes, the presence of the lactose molecule controls whether the operon is on or off.

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d statement

explanation:

1. desertification

2. captive breeding

3. black rhinoceros

4. renewable resources

explanation:

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