Biology / Unit 6 Bio 1317 short lesson, about 20 seconds
The lac Operon: Inducible Regulation
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The idea
The lac operon is inducible: when lactose is present, its metabolite binds the lac repressor, releasing it from the operator and permitting transcription.
In practice
Allolactose binds the lac repressor, changing its shape so it can no longer bind the operator, letting polymerase transcribe the lactose genes.
Where people slip
Repressor release only permits transcription — full activity needs glucose scarce, reverse from the trp operon's shutoff.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
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