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In the presence of lactose an inducer molecule binds to the lac repressor molecule. the lac...

In the presence of lactose

an inducer molecule binds to the lac repressor molecule.
the lac repressor binds to the operator.
genes of the lac operon are not expressed.
all of the choices.
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Answer #1

Answer: An inducer molecule binds to the lac repressor molecule.

When lactose is present in the medium the lactose changes to allolactose which acts as an inducer molecule. The inducer molecule is then binds with the repressor molecule due to which the repressor gets inactive and doesn't bind with the operator. Then the polymerase enzyme transcribes the operon gene whose products help in the digestion of the lactose molecule.

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