The isoelectric point is a

Given below are two statements,one is labelled as Assertion $A$ and the other is labelled as Reason $R$.
Assertion $A$: $A$ solution of the product obtained by heating a mole of glycine with a mole of chlorine in the presence of red phosphorus generates a chiral carbon atom.
Reason $R$: $A$ molecule with $2$ chiral carbons is always optically active.
In the light of the above statements,choose the correct answer from the options given below:

If the side chain group $-R$ for an amino acid is $-CH_{2}OH$,identify the amino acid from the following:

Serine $(HOCH_2CH(NH_2)COOH)$ is an amino acid. The correct Fischer projection of $L$-serine is:

When $HNO_3$ is dropped into the palm and washed with water,it turns yellow. The above yellow colour is due to:

In the primary structure of proteins,the amino acids are interconnected by-