Question

Match the following genes of the lac operon with their respective products.

Column 1	Column 2
I gene	β-galactosidase
z gene	Permease
A gene	Repressor
Y gene	Transacetylase

Answer 1

A. I gene (III)Repressor

1. The lac-operon is a group of genes.
2. This group of genes is responsible for the metabolism and transport of Lactose in E.coli.
3. I gene codes for a repressor protein.
4. The I in the name stands for Inducer.
5. It has the ability to turn off the expression of the gene, and it prevents the formation of messenger RNA.

B. Z gene (I)β-galactosidase

1. The z gene codes for beta-galactosidase.
2. This gene is responsible for the catalysis of the hydrolysis of lactose into glucose and galactose.

C. A gene (IV) Transacetylase

1. The lac A gene codes for β-galactoside transacetylase.
2. Its function is to facilitate the functioning of- galactosidase by transferring an acetyl group from Acetyl-CoA to galactosidase necessary for lactose catabolism.

D. Y gene (II) Permease

1. The y gene is which codes for the permease enzyme.
2. It facilitates and regulates the permeability of lactose into the cells.

	Column I		Column II
A.	I gene	(iii)	Repressor
B.	Z gene	(i)	β-galactosidase
C.	A gene	(iv)	Transacetylase
D.	Y gene	(ii)	Permease