In the lac operon, what happens when lactose is present?
Answer and explanation
Correct answer: B. It binds the repressor so that transcription can proceed
- Step 1: Lactose, via allolactose, inactivates the repressor and the genes are expressed. Answer: It binds the repressor so that transcription can proceed. Why not the others: It binds the promoter and blocks RNA polymerase, It degrades the operator and It increases glucose uptake don't fit.
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