| A | B |
|---|
| Nitrogen fixation | process by which gaseous nitrogen is converted into nitrates by the nitrogen-fixing bacteria |
| Nitrification | ammonia is converted into nitrates by nitrifying bacteria |
| Denitrification | denitrifying bacteria break down nitrogen compounds and release nitrogen gas into the atmosphere |
| Ammonification | decomposition of organic nitrogen compounds to ammonia |
| Assimilation | nitrates, ammonia, or ammonium absorbed by roots and used to make organic nitrogen compounds |
| Nitrogen Cycle | nitrogen cycles between the abiotic environment and organisms |
| Importance of nitrogen | nitrogen is needed by all living things, because it is part of the structure of amino acids and proteins |
| Five Steps in Nitrogen Cycle | nitrification, denitrification, nitrogen fixation, ammonification, assimilation |
