In the absence of glucose, how does the lac operon function when lactose is present?
A) Lactose binds to the repressor protein and alters its shape so it can no longer bind to the operator. RNA polymerase is then able to bind to the promoter and transcribes genes necessary for metabolizing lactose.
B) Lactose binds to the operator, preventing the repressor protein from binding to the promoter. RNA polymerase is then able to bind to the promoter and transcribes the genes necessary for metabolizing lactose.
C) A repressor protein binds to the operator, which prevents RNA polymerase from binding to the promoter.
D) A repressor protein binds to the operator, preventing lactose from binding to the operator. RNA polymerase then binds to the lactose and breaks it down.
E) Lactose binds to a repressor protein. The repressor protein then binds to RNA polymerase, which metabolizes the lactose and dismantles the repressor protein.
A) Lactose binds to the repressor protein and alters its shape so it can no longer bind to the operator. RNA polymerase is then able to bind to the promoter and transcribes genes necessary for metabolizing lactose.
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