Identify the odd one out.

Identify the physical and chemical processes from the following:
$I - Ba(OH)_2 + H_2SO_4 \rightarrow BaSO_4 + 2H_2O$
$II -$ Ice $\rightarrow$ Water
$III -$ Water $\rightarrow$ Steam
$IV -$ Starch $\rightarrow$ Glucose
Which of these represent physical processes and chemical processes respectively?

$A$ chemical substance acts as the currency of energy metabolism in a cell. It is:

Select the correct match for $X$ and $Y$.

Column $X$	Column $Y$
$(1)$ Starch	$(P)$ Found in animal skeletal tissues
$(2)$ Glycogen	$(Q)$ Stored food form in plants
$(3)$ Chitin	$(R)$ Provides strength in sclerenchyma
$(4)$ Lignin	$(S)$ Stored food form in animals

...... is known as the anti-sterility vitamin.

In which one of the following is nitrogen not a constituent?