Zoology - Molecular Basis of Inheritance Question with Solution | TestHub

The lactose or lac operon ofEscherichiacoliis a cluster of three structural genes encoding proteins which is involved in lactose metabolism and the sites on the DNA taking part in regulation of the operon. The three genes are:$\left(\mathrm{A}\right)$lacZ: it encodes for enzyme β-galactosidase (which splits lactose into glucose and galactose);$\left(\mathrm{B}\right)$lacY: it encodes for lactose permease; and$\left(\mathrm{C}\right)$lacA: It encodes for lactose transacetylase. Functional β-galactosidase and lactose permease are necessary for the usage of lactose by this bacterium. The concentration of these proteins are in low quantity when the organism is grown on carbon sources other than lactose.