The switching on and off of the lac operon is | vedclass

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(D) The $lac$ operon is an inducible operon system. In the absence of an inducer (lactose),the repressor protein binds to the operator region,preventi

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Inducer

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(D) The $lac$ operon is an inducible operon system. In the absence of an inducer (lactose),the repressor protein binds to the operator region,preventing $RNA$ polymerase from transcribing the structural genes,thus keeping the operon 'switched off'. In the presence of an inducer (lactose or allolactose),the inducer binds to the repressor protein,causing a conformational change that prevents the repressor from binding to the operator. This allows $RNA$ polymerase to transcribe the structural genes,effectively 'switching on' the operon. Therefore,the presence or absence of the inducer is the primary factor regulating the switching on and off of the $lac$ operon.

Column-$I$	Column-$II$
$(i)$ Operator site	$(a)$ Codes for enzyme (protein)
$(ii)$ Promoter site	$(b)$ Codes for repressor
$(iii)$ Structural gene	$(c)$ Binding site for $RNA$ polymerase
$(iv)$ Regulator gene	$(d)$ Binding site for repressor

The switching on and off of the $lac$ operon is regulated by which of the following?

Similar Questions

Identify the $INCORRECT$ statement from the following with reference to lac operon.

Match Column-$I$ with Column-$II$:

Column-$I$ Column-$II$

$(i)$ Operator site $(a)$ Codes for enzyme (protein)

$(ii)$ Promoter site $(b)$ Codes for repressor

$(iii)$ Structural gene $(c)$ Binding site for $RNA$ polymerase

$(iv)$ Regulator gene $(d)$ Binding site for repressor

Which of the following is true for a repressible operon?

Which of the following is a regulatory gene?

Wild-type $E. coli$ cells are grown in a normal medium containing glucose. They are then transferred to a medium containing only lactose as the sugar source. Which of the following changes will occur?

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