Question

explain the nitrogen cycle...diagram too

Answer 1

It is the cyclic process by which nitrogen changes from its elemental form present in atmosphere to simple molecules that enter living beings and form complex molecules. These complex molecules are then broken down again to release nitrogen back to atmosphere.
Nitrogen cycle involves following steps -

1) Nitrogen fixation --- Atmospheric nitrogen is converted to water soluble nitrates and nitrites . This is done by nitrogen fixing bacteria like azotobacter, rhizobium..

2) Nitrogen assimilation --- Plants absorb soluble nitrate ion and form amino acids, that are used for making proteins.Animals take organic nitrogen from plants directly or indirectly.

3)Ammonification --- It is the process of ammonia formation by decomposition or breakdown of dead and complex organic matter .This is done by microorganisms living in the soil ...for example -- purifying bacteria.

4) Nitrification --- It is the process of conversion of ammonia into nitrites and then to nitrates by nitrifying bacteria.

5) Denitrification ---- It is the process of reducing nitrates or ammonia present in soil to molecular nitrogen that gets back into atmosphere.This is done by microorganism like Pseudomonas

Hope This Helps You!

Answer 2

The nitrogen cycle is the biogeochemical cycle by which nitrogen is converted into various chemical forms as it circulates among the atmosphere and terrestrial and marine ecosystems. The conversion of nitrogen can be carried out through both biological and physical processes. Important processes in the nitrogen cycle include fixation, ammonification, nitrification, and denitrification. The majority of Earth's atmosphere (78%) is nitrogen,[1] making it the largest pool of nitrogen. However, atmospheric nitrogen has limited availability for biological use, leading to a scarcity of usable nitrogen in many types of ecosystems. The nitrogen cycle is of particular interest to ecologists because nitrogen availability can affect the rate of key ecosystem processes, including primary production and decomposition. Human activities such as fossil fuel combustion, use of artificial nitrogen fertilizers, and release of nitrogen in wastewater have dramatically altered the global nitrogen cycle.[2]