The nitrogen cycle is how nitrogen moves through the atmosphere.
The nitrogen cycle uses different things to move the nitrogen around.
Nitrogen is important to anything that is living on the Earth.
Unlike oxygen, nitrogen is not absorbed from the air by plants or animals.
Nitrogen moves through different things such as:
Nitrogen has different forms on the Earth. There are different states of the nitrogen such as:
In order for the nitrogen cycle to work, the most important part is bacteria.
Bacteria helps the nitrogen to change to different states so that it can be used in the right way.
Soil, for example, has bacteria that helps the nitrogen be broken down so that it can be absorbed.
Animals get nitrogen from the plants.
There are different steps in the nitrogen cycle and these steps include:
Fixation is when bacteria turns nitrogen into ammonium so that it can be used by plants.
Nitrification is the process where bacteria changes the ammonium to nitrates and the plants absorb these nitrates.
Assimilation is when the plants absorb the nitrates from the soil and from their roots. The nitrogen is then used for chlorophyll, nucleic acids and amino acids.
Ammonification is when the plant or animal dies and the decomposers turn the nitrogen back into ammonium and then it returns to the nitrogen cycle. Remember that decomposers are bacteria and fungi.
Denitrification is when bacteria sends more nitrogen into the soil and the nitrogen is released into the air.
People, plants or animals cannot live without nitrogen.
Nitrogen helps to make up cells and helps to produce things such as proteins, amino acids and other things that are needed for our bodies. Many of the things that nitrogen produces are found in our DNA.
Another reason that nitrogen is so important is that it is needed by animals, plants and people because it helps to build things in our bodies that are the building blocks of life.
Nitrogen also helps with the process of chlorophyll which is needed for photosynthesis to help plants grow.
The nitrogen cycle gets changed when people add fertilizers to the soil.
Since fertilizers have nitrogen in them, adding it into the fertilizer causes the plants to release a gas called nitrous oxide.
When adding more nitrogen to the Earth, it causes more nitrogen than is needed into the Earth and changes the nitrogen cycle.