Which of the following foodstuffs contains nitrogen?

The isoelectric point of alanine is $pH = 6$. At which $pH$ will the maximum concentration of the zwitterion of alanine be present?

$A$ nanopeptide contains $\dots$ peptide linkages.

What does the secondary structure of proteins represent?

Assertion $(A)$: In aqueous solution,amino acids exist in dipolar ion form.
Reason $(R)$: Most of the naturally occurring amino acids have $L$-configuration.
The correct option among the following is:

Which of the following is $NOT$ a basic amino acid?