Nitrogen is essential for all life on this planet, but most of it is in the air, making up about 78% of the earths atmosphere. The growth of all organisms depends on the availability of mineral nutrients, and none is more important than nitrogen, which is required in large amounts as an essential component of proteins, nucleic acids and other cellular constituents. There is an abundant supply of nitrogen in the earth's atmosphere in the form …showed first 75 words of 961 total…

…showed last 75 words of 961 total…the body. Here they are built up again into proteins. Excess amino acids are deaminated in the liver, where the nitrogen becomes part of urea molecules. These are excreted in urine. All life requires nitrogen-compounds, all organisms require nitrogen to live and grow. It is abundant in the atmosphere and in soil organic matter however most organisms cannot use nitrogen in this form that is why nitrogen fixation is so important to all life forms.