Question

Which one is disaccharide?
A) Glucose
B) Cellulose
C) Maltose
D) Ribose

Answer 1

Hint: On hydrolysis with acids or enzymes the carbohydrates give two molecules of monosaccharides which can either be different or same so that carbohydrates are called disaccharides. After the loss of water molecules the oxide linkage is formed and then the two monosaccharides are formed by that linkage.

Complete answer:
A disaccharide is also called a double sugar. These are added as sweeteners in many foods. Plants also store energy in the form of disaccharides like sucrose and it is also used for transporting nutrients in the phloem.
Glucose is a monosaccharide having an aldehyde group and are called aldolases. These have six carbon atoms per molecule.
Cellulose is a fibrous polysaccharide with a high tensile strength. A cellulose molecule consists of an unbranched and linear chain of 6000 or more glucose residues.
Maltose is a biologically important disaccharides and also known as malt sugar. It is found in germinating seeds where starch is being broken down. It is formed of two molecules of glucose and called a reducing sugar.
Ribose is a monosaccharide having an aldehyde group and is called aldolases. These are simple carbohydrate monomers having five carbon atoms per molecule.

So, the correct answer is option (C) Maltose.

Note: Disaccharides are the smallest and commonest oligosaccharides in the cells. They are formed by the condensation of two monosaccharides molecules. Biologically important disaccharides are sucrose (also called as table sugar obtained from sugarcane and sugar beet), lactose (also called as milk sugar and found naturally in mammalian milk), maltose (also known as malt sugar and found in germinating starchy seeds) and trehalose (it is found in some fungi and haemolymph of some insects).