JEE Main · 2021 · 20 Jul 2021 · Shift 1 · Biomolecules

Identify the incorrect statement from the following:

(A) $β$ -Glycosidic linkage makes cellulose polymer
(B)Amylose is a branched chain polymer of glucose✓ Correct
(C)Starch is a polymer of $α$ - D glucose
(D)Glycogen is called as animal starch

Answer: (B)

Solution

Amylose is the linear component of starch: its

α

-D-glucose units are joined only by

α (1 \to 4)

linkages, and the

α (1 \to 6)

branch points belong to amylopectin, the other component. The remaining statements hold: cellulose is built from

β

-D-glucose units linked

β (1 \to 4)

, starch is a polymer of

α

-D-glucose, and glycogen, the storage carbohydrate of animals, is called animal starch. The incorrect statement is that amylose is a branched chain polymer of glucose.

JEE Main · 2021 · 20 Jul 2021 · Shift 1 · Single correct option

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