Nitrogen

Nitrogen is a colorless, odorless gas that makes up about 78% of Earth's atmosphere. It is essential for all living organisms because it is a key component of amino acids and nucleic acids, which build proteins and DNA. Nitrogen usually exists as N₂ molecules, which are very stable and not reactive under normal conditions. In nature, nitrogen cycles through the environment via processes like fixation, where bacteria convert it into forms plants can absorb. Humans also use nitrogen in industrial applications, such as producing fertilizers, to promote plant growth. Overall, nitrogen is vital for life and the environment.