JEE Main Chemistry Question (2026) — Solution

Step-by-step solution

The tertiary structure of proteins represents the overall folding of the polypeptide chains, which is the further folding of the secondary structure. This folding gives rise to two major molecular shapes: fibrous and globular. The main forces that stabilize the secondary and tertiary structures of proteins are hydrogen bonds, disulphide linkages, van der Waals forces, and electrostatic forces of attraction. When a protein in its native form is subjected to physical changes like temperature or chemical changes like pH, the hydrogen bonds and other stabilizing forces are disturbed. Due to this, globules unfold and the helix gets uncoiled, causing the protein to lose its biological activity. This process is called denaturation of the protein. Thus, the tertiary structure does not remain intact when exposed to pH changes. Answer: The structure remains intact when exposed to pH changes.