Nutrient cycles

2. Burned as fossil fuels that include coal and natural gas.
3. Nitrogen-_____ bacteria.
6. fuels Burning these releases more CO2 in the atmosphere.
8. The water cycle is condensation, precipitation, and…?
10. Phosphorus in soil can be washed away into water…?
12. The main regulator of CO2.
13. Phosphorus is an essential nutrient because it makes up important chemicals such as…?
14. A source of too much phosphorus in water.
16. The process animals use to convert oxygen into more CO2.
17. Our atmosphere is made out of 78% of what gas?
19. Another natural source for this is volcanoes.
20. Higher organisms use nitrogen to make their…?

1. The type of bacteria in the soil that breaks down ammonia.
4. The process plants use to convert CO2 into sugar and oxygen.
5. Too much phosphorus in water leads to plant…?
7. Phosphorus is contained mostly in rocks and…?
9. Animals and plants cannot directly use all the nitrogen found in our…?
11. Animal waste decay by the action of bacteria creates _____ and nitrate products.
15. Too much CO2 in the atmosphere may be responsible for the… effect.
18. As dead plants and animals decayed huge deposits of… were stored.