Most common types of secondary structures of proteins are :

Options

A. `alpha`-helix and `beta-`helix structures
B. `alpha`-helix and `beta`-pleated sheet structures
C. right and left hand twisted structures
D. globular and fibrous structures

Answer

B

Explanation

Due to regular folding of backbone of the peptide chain, two most common secondary structures of proteins are `alpha`-helix and `beta`-pleated structures. In `alpha`-helix, all H-bonds are formed by twisting the chain into a right handed helix, In `beta`-pleated , all peptide chains are stretched to maximum extension and then laid side by side connected by hydrogen bonds.