Question

Lactose is made of

• A. $\alpha $ -D-galactose and $\beta $ -D-glucose
• B. $\alpha $ -D-glucose and $\beta $ -D-glucose
• C. $\beta $ -D-galactose and $\beta $ -D-glucose
• D. $\beta $ -D-galactose and $\alpha $ -D-glucose

Answer 1

Answer: (C)

Lactose (milk sugar) is a disaccharide, which is obtained by the condensation of one molecule of $\beta $ -D-galactopyranose and one molecule of $\beta $ -D-glucopyranose.