In the tryptophan operon,which of the followi | vedclass

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(D) The tryptophan $(trp)$ operon is an example of a repressible operon involved in an anabolic pathway (biosynthesis of tryptophan).$1$. The $R$-gene

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Enzymes produced by structural genes are normally present in the cell.

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(D) The tryptophan $(trp)$ operon is an example of a repressible operon involved in an anabolic pathway (biosynthesis of tryptophan).$1$. The $R$-gene (regulatory gene) produces an inactive protein called an aporepressor,which is proteinaceous,not non-proteinaceous. Thus,option $A$ is incorrect.$2$. In the presence of tryptophan (the corepressor),the aporepressor becomes active and binds to the operator,preventing the conversion of chorismic acid to tryptophan. However,under normal conditions (when tryptophan is absent),the operon is active,and chorismic acid is converted into tryptophan. Thus,option $B$ is incorrect.$3$. The $trp$ operon is an anabolic pathway (building up molecules),not a catabolic pathway. Thus,option $C$ is incorrect.$4$. In the absence of tryptophan,the structural genes are transcribed and translated to produce enzymes that are normally present in the cell to facilitate the synthesis of tryptophan. Thus,option $D$ is the correct statement.

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

In the tryptophan operon,which of the following statements is correct?

Similar Questions

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

What does '$4$' represent in the given figure?

The $lac \, y$ gene codes for which of the following?

Assertion $(A):$ Regulation of $lac$ operon by repressor is referred to as negative regulation.
Reason $(R):$ Repressor protein binds to the operator region and prevents $\text{RNA}$ polymerase from transcribing the operon.

Which of the following statements is correct regarding the repressor of the $lac$-operon?

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