Identify the amino acid which has $-NH_2$,$-CO_2H$ and $-CONH_2$ groups.

Consider the following statements:
Statement-$I$: The primary structure of a protein represents its amino acid sequence.
Statement-$II$: The $\alpha$-helix and $\beta$-pleated sheet structures of a protein represent its tertiary structure.

When proteins are heated with concentrated $HNO_3$,a yellow color is obtained. What is this test called?

Subunits present in haemoglobin are

Which one of the following statements is correct?

Column-$I$	Column-$II$
$A$. Tyrosine	$P$. Essential amino acid
$B$. Serine	$Q$. Ceric Ammonium Nitrate
$C$. Tryptophan	$R$. Neutral $FeCl_{3}$
$D$. Proline	$S$. Carbylamine Test - Negative

Select the correct set of answer :