Match the Column 1 with Column 2 :
| Column1 | Column 2 |
| 1) z gene | a) Permease |
| 2) y gene | b) Transacetylase. |
| 3) a gene | c) Repressor |
| 4) i gene | d) Beta-galactosidase (β-gal) |
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) - 1-d,2-a,3-b,4-c.
| Column1 | Column 2 |
| 1) z gene | d) Beta-galactosidase (β-gal) |
| 2) y gene | a) Permease |
| 3) a gene | b) Transacetylase. |
| 4) i gene | c) Repressor |
The lac operon consists of one regulatory gene (the i gene – here the term i does not refer to inducer, rather it is derived from the word inhibitor) and three structural genes (z, y, and a). The i gene codes for the repressor of the lac operon. The z gene codes for beta-galactosidase ( β-gal), which is primarily responsible for the hydrolysis of the disaccharide, lactose into its monomeric units, galactose and glucose. The y gene codes for permease, which increases permeability of the cell to β-galactosides. The a gene encodes a transacetylase. Hence, all the three gene products in lac operon are required for metabolism of lactose