Read the passage carefully and answer.
Carbohydrates are essential for both plants and animals. Some common examples of carbohydrates are glucose, fructose, sucrose, glycogen, cellulose and starch. They form a major portion of our food. Honey has been used for a long time as an instant source of energy in Ayurvedic medicine. Carbohydrates are used as storage molecules in both plants and animals. The cell wall of bacteria and plants is made of cellulose. We use cellulose in the form of wood for making furniture and as cotton fiber for clothing. They also provide raw material for textiles, paper, lacquers, and breweries. Carbohydrates are classified as Monosaccharides, Oligosaccharides and Polysaccharides on the basis of their behavior towards hydrolysis. Monosaccharides cannot be hydrolyzed further to simpler units whereas oligosaccharides can yield 2-10 units of monosaccharides on hydrolysis. Polysaccharides, which are non-sugars yield a large number of monosaccharide units on hydrolysis.
Answer the following questions about carbohydrates:
The sugar having β-glycosidic linkage is
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → Cellulose
A glycosidic linkage is the C–O–C bond that joins two monosaccharide units after the loss of a water molecule. Whether it is an α or a β linkage depends on the form of the sugar unit whose C1 takes part: an α-D-glucose unit gives an α-glycosidic linkage, a β-D-glucose unit a β-glycosidic linkage.
Cellulose is a straight chain polysaccharide made only of β-D-glucose units, joined from C1 of one unit to C4 of the next. So cellulose is the one with the β-glycosidic linkage. Starch, glycogen and maltose are all built from α-D-glucose units.
Why the other options are incorrect
Option (1) Starch — Incorrect. Both its components are polymers of α-D-glucose: amylose has C1–C4 α-linkages, and amylopectin has C1–C4 α-linkages in the chain and C1–C6 at the branches.
Option (2) Glycogen — Incorrect. Its structure is like amylopectin, only more highly branched, so its linkages are α-linkages too.
Option (4) Maltose — Incorrect. It is two α-D-glucose units joined from C1 of one to C4 of the other, an α-1,4-glycosidic linkage.
NCERT (2026-27 edition):
Cellulose
