The most important energy carrier in all the living cells is

The secondary structure of proteins is stabilized by which bond?

Given below are two statements $:$
Statement $(I):$ On hydrolysis,oligopeptides give rise to a fewer number of $\alpha$-amino acids,while proteins give rise to a large number of $\beta$-amino acids.
Statement $(II):$ Natural proteins are denatured by acids,which convert the water-soluble form of fibrous proteins to their water-insoluble form.
In the light of the above statements,choose the most appropriate answer from the options given below $:$

An example of a sulphur-containing amino acid is:

Assume that a particular amino acid has an isoelectric point of $6.0$. In a solution at $pH$ $1.0$,which of the following species will predominate?

Which of the following amino acids is basic in nature?