Describe Nitrogen Cycle-Nitrogen cycle in simple terms

The atmosphere is 78% nitrogen, which is essential for DNA and proteins. However, humans cannot directly breathe nitrogen like oxygen; instead, it must be absorbed through food. Nitrogen follows a continuous cycle from the atmosphere to the soil, to animals, and back.

Atmospheric nitrogen reaches Earth via precipitation (rain or snow). Once in the soil, specific bacteria on plant roots combine nitrogen with hydrogen to form ammonia in a process called nitrogen fixation. Lightning can also contribute to this process.

Ammonia is toxic, so additional bacteria convert it with oxygen into nitrite through nitrification. Further nitrifying bacteria then transform nitrite into nitrate. At this stage, plants can absorb this nitrogen via assimilation.

Not all nitrate is absorbed by plants. Some is taken up by bacteria that release nitrogen back into the atmosphere through denitrification, completing the atmospheric return part of the cycle.

After animals consume plants, the nitrogen within them eventually returns to the soil through death or waste. Decomposers and specific bacteria break down this nitrogen in waste or dead animals through ammonification, allowing it to re-enter the cycle at the nitrification stage, thereby continuing the nitrogen flow.