The cycles

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Across
  1. 3. higher organisms use nitrogen to make their…
  2. 7. water that is in the ground
  3. 10. we add nitrogen to soil by using…
  4. 11. what is the main regulator of CO2 in the atmosphere
  5. 14. groundwater taken to the atmosphere
  6. 17. rain, snow, sleet, or hail
  7. 19. the process from turning liquid into vapor
  8. 20. animals use oxygen in this process to make more CO2…
  9. 21. another natural source for CO2 is…
Down
  1. 1. phosphorus is not found in the free state in nature but is found in rocks and…
  2. 2. another source of phosphorus in water comes from man made…
  3. 4. too much CO2 in the atmosphere may be responsible for…
  4. 5. eight our atmosphere is how many percent nitrogen gas
  5. 6. bacteria in the soil can break down ammonia into the gaseous form of nitrogen
  6. 8. some of the phosphorus in soils can be washed into water…
  7. 9. to much phosphorus can lead to plant…
  8. 12. plants use CO2 in the process of photosynthesis to make
  9. 13. conversion of vapor to a liquid
  10. 15. animal waste and decay by the action of bacteria create ammonia and…
  11. 16. it is essential because it helps make up an impact chemical called…
  12. 18. animals and plants can not directly use nitrogen found in our…