Q.Explain the secondary structure of protein with examples.

Step 1. Secondary structure arises when hydrogen bonds form at regular intervals between different parts of a polypeptide chain (or between neighbouring chains), causing it to coil or fold in a repeating pattern.

Step 2. One common secondary structure is a helical coil: a right-handed coil is called an alpha-helix; hair keratin is a well-known example of a protein whose polypeptide chain is arranged as an alpha-helix.

Step 3. A left-handed coil is called a beta-helix. …

Explain how hydrogen bonding produces the alpha-helix/beta-helix/pleated-sheet secondary struc …

• Confusing secondary structure (local, hydrogen-bond-based coiling) with tertiary structure (the overall 3-D fold of the whole chain, often disulphide-stabilised). …