When lactose is first introduced into the medium, the lac operon is not induced and thus permease isn't induced. How it is possible for lactose to enter the cell before the lac operon is induced?
What will be an ideal response?
While the lac operon is not induced yet, there is low level expression most of the time which allows a small amount of permease to be expressed. This allows lactose to enter the cell at low levels until the lac operon is needed for full induction.
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