Ques. 1NEET (UG) 2022 (Phase 2)
The incorrect statement about denaturation of proteins is :
- Uncoiling of the helical structure takes place
- It results due to change of temperature and/or pH
- It results in loss of biological activity of proteins
- A protein is formed from amino acids linked by peptide bonds
Answer
(4) A protein is formed from amino acids linked by peptide bonds
Solution
As per NCERT, when a protein in its native form is subjected to physical change like change in temperature or chemical change like change in pH, the hydrogen bonds are disturbed. Due to this, globules unfold and helix gets uncoiled and protein loses its biological activity. This is called denaturation of protein. During denaturation, 2° and 3° structures are destroyed but 1° structure remains intact.
(1), (2) and (3) correctly describe denaturation; statement (4) only describes the primary structure of a protein and is not a statement about denaturation.
Answer: (4)