Sucrose is composed of $......$.

Which of the following is a dimer?

Which characteristic distinguishes a disaccharide from a monosaccharide?

Aqueous solution of carbohydrate with $2$ drops of alcoholic solution of $\alpha$-naphthol and $H_{2}SO_{4}$ gives a ring at the junction. The colour of the ring is:

Which polysaccharide consists of both branched and unbranched chain molecules?

Statement $X$: Starch is the stored food in plants.
Statement $Y$: Glucose is the stored food in animals.