In the lac operon,which enzyme(s) will be pro | vedclass

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Question

(A) The $lac$ operon consists of three structural genes: $lac$ $z$,$lac$ $y$,and $lac$ $a$.$lac$ $z$ codes for $\beta$-galactosidase,$lac$ $y$ codes f

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$\beta$-galactosidase

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(A) The $lac$ operon consists of three structural genes: $lac$ $z$,$lac$ $y$,and $lac$ $a$.$lac$ $z$ codes for $\beta$-galactosidase,$lac$ $y$ codes for lactose permease,and $lac$ $a$ codes for transacetylase.$A$ nonsense mutation in the $lac$ $y$ gene introduces a premature stop codon,which terminates the translation of the lactose permease protein.Since the genes in the $lac$ operon are transcribed as a single polycistronic mRNA,the mutation in $lac$ $y$ prevents the translation of downstream genes ($lac$ $a$) due to the premature termination of the ribosome.However,the $lac$ $z$ gene is located upstream of the $lac$ $y$ gene and is translated independently before the ribosome reaches the mutated $lac$ $y$ site.Therefore,only $\beta$-galactosidase (encoded by $lac$ $z$) will be produced,while lactose permease and transacetylase will not be produced.

In the $lac$ operon,which enzyme$(s)$ will be produced in the cell if there is a nonsense mutation in the $lac$ $y$ gene?

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