The atmosphere is composed mainly of nitrogen and oxygen. Together they make up about 99% of clean, dry air. Nitrogen 78% and oxygen 21%. Apart from these two major gases, there are other gases too in the atmosphere. These gases include carbon dioxide, argon and others comprise 1% by volume. Oxygen is the breath of life while nitrogen helps in the growth of living organisms. Carbon dioxide absorbs heat radiated by the earth. In this way, it keeps the planet warm. It is also essential for the growth of plants.
