Subunits present in haemoglobin are

Observe the structures of the following compounds:
$1$. $2$-chlorobutane
$2$. Glycine $(NH_2CH_2COOH)$
$3$. Alanine $(CH_3CH(NH_2)COOH)$
$4$. Styrene $(C_6H_5CH=CH_2)$
$5$. Menthol
The total number of structures/compounds which possess asymmetric carbon atoms is $....$

Which of the following amino acids contains an imidazole ring?

Which one of the following is a globular protein?

Assume that a particular amino acid has an isoelectric point of $6.0$. In a solution of $pH$ $1.0$,which of the following species will predominate?

Assertion : Proteins on hydrolysis produce amino acids.
Reason : Amino acids contain $-NH_2$ and $-COOH$ groups.