The atmosphere is full of nitrogen gas (N2). But plants cannot use nitrogen in this form. Summarize the roles of bacteria in making nitrogen available to plants and in returning nitrogen to the atmosphere.

Explanation:

Since plants cannot make use of nitrogen in this form, they need the help of some organisms which are Bacteria; nitrifying bacteria etc o help in the conversion of this form of nitrogen to that particular form mostly nitrates they can utilize directly.

Thus, most nitrogen is collected from the atmosphere and fixed by microorganisms such as bacteria to form ammonia, nitrites, and nitrates that can be used by plants. These organisms make use of the enzyme nitrogenase to aid in the conversion of atmospheric nitrogen (N2) to ammonia (NH3).

Nitrogen is returned to the atmosphere by denitrification which is the opposite if nitrification and is carried out by denitrifying bacteria. Nitrate is reduced to nitrogen through the production of some intermediate products.

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