Could someone concisely and briefly summarize the nitrogen cycle? I'm all in a muddle. Please, I have to get this done by tonight.
en.wikipedia. org/wiki/Nitrogen_cycle
http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/N/NitrogenCycle.html
en.wikipedia. org/wiki/Nitrogen_cycle
http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/N/NitrogenCycle.html