question_answer

Which one of the following statements is not true regarding (+) lactose?              [AIPMT (S) 2011]

A) (+) lactose is a \[\text{ }\!\!\beta\!\!\text{ -}\]glycoside formed by the union of a molecule of D(+) glucose and a molecule of D(+) galactose

B) (+) lactose is a reducing sugar and does not exhibit mutarotation

C) (+) lactose,\[{{C}_{12}}{{H}_{22}}{{O}_{11}}\]contains 8-OH groups

D) On hydrolysis (+) lactose gives equal amount of D (+) glucose and D (+) galactose

Correct Answer: B

Solution :

[b]

Lactose is a reducing sugar and all reducing sugars show autorotation.