Question

Which of the following is incorrect regarding maltose?

• A. It consists of two glucopyranose units
• B. It is a non-reducing sugar
• C. Glycosidic bond between C1 of one unit and C4 of the other unit
• D. It is a disaccharide

Answer 1

The correct option is B It is a non-reducing sugar

Maltose is a dissacharide. Hydrolysis of maltose gives two monomers of glucose.
$C_{12}{H}_{22}{O}_{11}\stackrel{\text{Hydrolysis}}{\to }{C}_6{H}_{12}{O}_6+C_6{H}_{12}{O}_6\text{Maltose}\alpha -D-\text{Glucose}\alpha -D-\text{Glucose}$

The free aldehyde group can be produced at the C1 carbon of the second α-D-glucose unit in solution and it shows reducing properties. Hence, it is a reducing sugar.
Glycosidic bond between C1 of one unit and C4 of the other unit