Question

Correct statement regarding primary structure of proteins is
(A) Primary structure represents the sequence of amino acids in a polypeptide chain.
(B) As long as the number and kind of amino acid units in a polypeptide chain are the same, any
change in the sequence of amino acids results in the same protein.
(C) When a protein is heated gently its primary structure gets destroyed.
(D)
R
Alkaline hydrolysis of a polypeptide gives amino acids in their cationic form, H.N
COOH
H​

Answer 1

Correct statement regarding primary structure of proteins is (A)

Explanation:

• Primary structure of a protein represents the linear sequence of amino acids connected to form a polypeptide chain. Statement (A) is correct.
• Statement (B) is false since , even if the number and kind of amino acids in a polypeptide is same, their bonding and attachment may vary and this will not result in the same protein.
• Statement (C) is also incorrect. Heating a protein may change its secondary, tertiary and quaternary structure but not necessarily its primary structure.
• Statement (D) is also false since acid hydrolysis of a polypeptide will yield positively charged ions.