Answer: In the Earth’s atmosphere, nitrogen is the most abundant gas. The gas oxygen is the second most plentiful. Diatomic molecules exist in each of these gases.
The atmosphere of the Earth is made up of 78 percent nitrogen, 21% oxygen, 1% argon, and trace amounts of carbon dioxide and neon.
Amino acids, proteins, DNA, and RNA all need nitrogen to function properly. For development, metabolic activities, and reproduction, all living species require nitrogen. Creatures get nitrogen from plants and other animals, which they eat.