1. Ricky & Gena

2.  In animal protein (organic)  In amino acids (organic)  In the soil  In the atmosphere

3.  By specialized bacteria converting nitrogen to ammonia and making it available to plants in soil and water  Also through lightning – this causes oxygen and nitrogen to react and create NO2

4.  1. Nitrogen Fixation  2. Nitrification  3. Ammonification  4. Denitrification

5.  Click the link to go to a site that explains the Nitrogen Cycle with captions. Animation #1  Click the link to go to a site that has a detailed animation explaining the Nitrogen Cycle. Animation #2

6. Specialized bacteria convert gaseous nitrogen to ammonia so it could be used by plants through the reaction : (N2 + 3H2  2NH3) Also through lightning

7. Ammonia in the soil is converted to nitrite ions (NO2-), by specialized bacteria. Nitrite ions are toxic to plants, but nitrate ions (NO3-) are nutrients for the plant.

8. Lots of decomposer bacteria convert the nitrogen-rich organic compounds like wastes, cast-off particles and dead bodies into simpler compounds like ammonia (NH3) and water soluble salts that have ammonium ions (NH4+).

9. Specialized bacteria like anaerobic bacteria in waterlogged soil, oceans, swamps and bottom sediments convert NH3 and NH4+ back into nitrite and nitrate and then into nitrogen gas and nitrous oxide gas.

10.  Burning fuels releasing amounts of nitric acid  Destroying grasslands and wetlands  Adding anaerobic bacteria to livestock wastes’  Agricultural runoff