Across
- 5. formed from the remains of dead plants and animals
- 6. animal waste becomes ammonia
- 7. live on the roots of some plants
- 9. water evaporating off the leaves of plants.
- 11. plants absorb CO2 and create C6H12O6 for animals.
- 12. dead organisms breaking down and returning carbon to the soil.
- 14. Water falls from the atmosphere in the form of rain, snow, or sleet
- 15. combining nitrogen and hydrogen to form ammonia.
- 17. water moves through soil into ground water.
Down
- 1. nitrate is changed to nitrogen gas and returned to atmosphere
- 2. water is heated by the sun into a gas state
- 3. animals breathe in oxygen and eat carbon. They breathe out CO2
- 4. water condenses from gas into liquid in clouds.
- 8. can change nitrogen to a usable form
- 10. plants absorb nitrogen.
- 13. the burning of fossil fuels
- 16. water runs into rivers ponds or oceans