Question

duplet tha lac operon and show the mechanism based on the principle of induction ?

Answer 1

Lac operon is an inducible operon that uses lactose as an energy source. It gets activated in presence lactose. In the absence of lactose the RNA polymerase do not transcribe the lac operon genes as repressor (inhibitor) is bound to operator (site adjacent to promoter where RNA polymerase binds). When lactose inducer is present it changes the shape of repressor molecule so RNA polymerase can bind operator (site adjacent to promoter where RNA polymerase binds) to initiate transcription.