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JEE Main · 2022 · 29 Jul 2022 · Shift 2 · Biomolecules

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Given below are two statements. One is labelled as Assertion A and the other is labelled as Reason R.

Assertion A: Amylose is insoluble in water.
Reason R : Amylose is a long linear molecule with more than 200 glucose units.

In the light of the above statements, choose the correct answer from the options given below.
  1. (A)Both and are correct and is the correct explanation of A.
  2. (B)Both and are correct and is NOT the correct explanation of A.
  3. (C) is correct but is not correct.
  4. (D) is not correct but is correct.✓ Correct

Answer: (D)

Solution

Amylose is actually water-soluble due to the presence of numerous hydroxyl groups that can form hydrogen bonds with water molecules. Therefore, Assertion A is incorrect. Reason R is correct: amylose is indeed a long linear polymer of glucose units (typically 200-1000 units) linked by α(1→4) glycosidic bonds. The correct answer is that A is not correct but R is correct.

JEE Main · 2022 · 29 Jul 2022 · Shift 2 · Single correct option

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