Question

which of the following scenerios occurs when lactose is present as the sole energy source A....

which of the following scenerios occurs when lactose is present as the sole energy source

A. the lac operon genes are not transcribed

B. the repressor protein binds to the operator

C. the enzymes for lactose metabolism are produced

D. production of the repressor protein is increased

Homework Answers

Answer #1

As we can see from the figure that when lactose is not present in the cell the lac operon is not able to transcribe as repressor protein binds to the operator site. As soon as lactose is available lactose is available to the cell, lactose binds to the repressor and initiate the lac operon transcription. which leads to a synthesis of enzymes responsible for lactose metabolism

As we can see from the figure that the transcription of lac repressor does not depend on presence f absence of lactose.

So option C. the enzymes for lactose metabolism are produced is the answer

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