Nitrogen Cycle

Nitrogen is the most abundant element on the earth.

Nitrogen makes of our atmosphere.

Also, nitrogen is present in many molecules which are essential to life.

Nitrogen is also found in other biological compounds like

So, Nitrogen is essential for all life forms and life would be simpler if all life forms can use nitrogen directly from the environment.

Let us learn the ways in which nitrogen is used by all type of life forms.

Only a few bacteria can use nitrogen directly from the environment.

And such type of bacteria is called .

These bacteria are generally found in the roots of legumes.

Apart from direct usage, it is converted into some other compounds.

Let us see how nitrogen is converted into other compounds.

Apart from nitrogen bacteria, the other way in which nitrogen molecule is converted into nitrates and nitrites is by physical process.

During lightning, the high temperature and pressure created in the air convert nitrogen into oxides.

And these oxides of nitrogen dissolves in water to give nitric and nitrous acids

This conversion of nitrogen in form of ammonium into nitrites and further into nitrates is called .

And these nitrous and nitric acid falls on the land along with rain and then utilized by various forms of life.

Let us see the usage of nitrates by various life forms.

Normally, plants convert these nitrates and nitrites into amino acids.

These amino acids are used by plants to make proteins.

Further, these proteins and other complex compounds are consumed by animals.

Once these animals and plants are dead, other bacteria convert these compounds of nitrogen into nitrates and nitrites.

A different type of bacteria converts these nitrates and nitrites into elemental nitrogen.

This process of converting nitrates into nitrogen is called .

This series of process in which nitrogen and its compounds are interconverted is known as the nitrogen cycle.

Let us learn about this nitrogen cycle.

Conversion of nitrogen from various forms to elemental form and vice versa is called the nitrogen cycle.


Nitrogen makes 78% of our atmosphere.

The Nitrogen cycle can be represented as above

The End