Thyroxine,adrenaline,and melanin pigment are derived from which of the following amino acids?

$A$ quaternary protein consisting of two $\alpha$-chains and two $\beta$-chains is:

Match the following columns regarding the representation of molecular structures:

Column-$I$ (Science)	Column-$II$ (Meaning of molecular structure)
$P$. Inorganic Chemistry	$I$. Molecular formula
$Q$. Organic Chemistry	$II$. Four levels of organization
$R$. Physics	$III$. Two-dimensional view
$S$. Biological Protein	$IV$. Three-dimensional view

$A$ conjugated protein containing carbohydrates is:

The given figure represents the structure of which molecule?

Find the correct option for the sequence given below:
$(1)$ Alanine $\rightarrow$ Valine
$(2)$ Asparagine $\rightarrow$ . . . . . .
$(3)$ Aspartic acid $\rightarrow$ Glutamic acid
$(4)$ Arginine $\rightarrow$ Histidine