Among the following,$L$-serine is

Find the isoelectric point $(pI)$ of the given amino acid: $HOOC-CH_2-CH_2-CH(NH_3^+)-COOH$. Given: $pK_{a1} = 2$,$pK_{a2} = 4$,$pK_{a3} = 9$.

Which of the following amino acids is $NOT$ synthesized in our body?

Which one of the following structures represents the peptide chain?

Stability of $\alpha$-Helix structure of proteins depends upon:

The general structure of $\alpha$-amino acid can be represented as shown below. Which amino acid is not correctly matched with the $R$ group given?