what is nitrogen cycle
The Nitrogen Cycle: Organisms require nitrogen to produce amino acids. Nitrogen makes up 70% of the atmosphere, but most organisms can not use this form of nitrogen, and must have the fixed form. The nitrogen cycle produces the fixed form of nitrogen these organisms need.
Step 1: The nitrogen fixing bacteria take atmospheric nitrogen and produce ammonia (NH3).
Step 2: Other bacteria use this ammonia to produce nitrates and nitrites, which are nitrogen and oxygen containing compounds.
Step 3: The nitrates and nitrites are used by plants to make amino acids which are then used to make plant proteins.
Step 4: Plants are consumed by other organisms which use the plant amino acids to make their own.
Step 5: Decomposers convert the nitrogen found in other organisms into ammonia and return it to the soil. A few of these types of bacteria return nitrogen to the atmosphere by a process called denitrification, however this amount is small.
