NEET2026BiologyChapterActual
In the lac operon of E. coli , what is the primary function of the product formed by the y gene?
Options
- ATo cleave the disaccharide lactose into galactose and glucose
- BTo increase the permeability of the cell to -galactosides
- CTo transfer an acetyl group to -galactosides
- DTo bind to the operator sequence and inhibit transcription
Correct answer
B. To increase the permeability of the cell to -galactosides
Step-by-step solution
The lac operon consists of three structural genes: z , y , and a . The z gene codes for -galactosidase, 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 the permeability of the cell to -galactosides, allowing lactose to enter the cell. The a gene codes for a transacetylase. Therefore, the primary function of the product formed by the y gene is to increase the permeability of the cell to -gala