Which of the following statement(s) is correct?
(A). Keratin is an example of fibrous protein.
(B). Fibrous proteins are water-soluble, while globular proteins are water-insoluble.
(C). Polypeptide chains in fibrous proteins run parallel and are held together by hydrogen and disulphide bonds.
(D). Insulin and albumins are common examples of globular proteins.
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → (A), (C), and (D) only
Proteins are classified by their molecular shape into fibrous and globular proteins.
(A) Keratin is an example of fibrous protein. — Correct. Keratin, the protein of hair, wool and silk, is fibrous, like myosin of muscles.
(B) Fibrous proteins are water-soluble, while globular proteins are water-insoluble. — Incorrect. The statement is the reverse of the facts: fibrous proteins are generally insoluble in water, while globular proteins are usually soluble.
(C) Polypeptide chains in fibrous proteins run parallel and are held together by hydrogen and disulphide bonds. — Correct. This parallel arrangement is what makes them fibre-like.
(D) Insulin and albumins are common examples of globular proteins. — Correct. Both have chains coiled into a compact, spherical shape.
NCERT (2026-27 edition):
Fibrous Proteins
