In the lac operon, the z gene codes for :
- the repressor of lac operon
- transacetylase
- permease
- beta-galactosidase
Answer
(4) beta-galactosidase
Solution
As per NCERT, the lac operon has one regulatory gene ( i) and three structural genes ( z, y and a).
i gene ⇒ repressor of the lac operon
z gene ⇒ beta-galactosidase (hydrolyses lactose into galactose and glucose)
y gene ⇒ permease
a gene ⇒ transacetylase
∴ The z gene codes for beta-galactosidase.
Answer: (4)