The total number of amino acids present in insulin is

The Zwitter ion among the following is

$1.78 \ g$ of an optically active $L$-amino acid $(A)$ is treated with $NaNO_{2} / HCl$ at $0^{\circ}C$. $448 \ cm^{3}$ of nitrogen at $STP$ is evolved. $A$ sample of protein has $0.25 \%$ of this amino acid by mass. The molar mass of the protein is

Among the following compounds,the most basic amino acid is:

Identify the neutral amino acid from the following list represented by three-letter symbols.

Which property of glycine distinguishes it from other naturally occurring amino acids?