Choose the correct option for human insulin.

Which of the following exists as a Zwitter ion?

Alanine and Phenylalanine are which type of amino acids?

$A$ - In the solution of different $pH$,the structure of amino acids changes.
$R$ - It is because of the ionisable nature of $-NH_2$ and $-COOH$ groups.

$A$: Each protein molecule is a polymer of amino acids.
$R$: There are $20$ types of amino acids in living cells.

Identify the structure of the amino acid shown in the image.