The atmosphere is composed
mainly of air molecules. And air molecules consist of 21% oxygen and 79%
nitrogen. Oxygen is used for a lot of things. It used for cellular respiration,
for humans to breathe and other complex chemical reactions that needs oxygen. Nitrogen
is one of the important nutrients mostly used in the soil of the plants. It is
used for protein synthesis. Nitrogen is also absorbed by the plants from the
and the soil to complete the necessary reactions.
