Give a brief description of how the nitrogen cycle works

Well, at first, special bacteria convert the nitrogen gas (otherwise known as N2) to ammonia (otherwise known as (NH3) so the plants can use it. Then, Nitrification. Nitrification is the process of converting the ammonia to nitrite ions which the plants can take in as nutrients. Third, after all the living organisms use the nutrients, the decomposer bacteria come and convert the nitrogen rich waste compounds to simpler ones. Fourth, and finally, other bacteria converts the simple nitrogen compounds back to nitrogen gas, (otherwise known as N2), which is then released back into the atmosphere to begin the cycle once more. 

I hope this helps! ~Mia