Cells prefer to use glucose over other energy sources. Therefore, in prokaryotes,
A) high levels of glucose will prevent expression from other operons that metabolize lactose.
B) low levels of glucose will cause the lactose mechanism to be turned off.
C) cAMP binds to activators to slow down transcription of the lac operon.
D) lactose will be synthesized only when there is ample glucose in the cell.
Answer: A) high levels of glucose will prevent expression from other operons that metabolize lactose.