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

(+) Lactose is a $$\beta $$-glucoside formed by the union of a molecule of D(+) glucose and a molecule of D(+) galactose.

(+) Lactose is a reducing sugar and does not exihibit mutarotation.

(+) Lactose, C₁₂H₂₂O₁₁ contains 8-OH groups

asymmetric carbons

primary alcoholic group

secondary alcoholic group

enolisation of fructose followed by conversion to aldehyde by base

(+) Sucrose

(+) Lactose

(+) Maltose

($$-$$) Fructose

ribose

gene

nucleoside

nucleotide