Across
- 4. process where nitrogen can enter food chain
- 5. rainwater runs along surface and collects
- 6. the basis for all living organisms
- 8. Plants and animals cannot form found in the ____.
- 10. excess fertilizers cause overgrowth of algae
- 11. organisms break down dead material
- 13. 2% of earth's freshwater is in ______
- 14. one organism eats another
- 17. Nitrogen in the atmosphere is in this form
- 18. sun heats liquid on surface that becomes vapor
- 20. process puts nitrogen back to N2
- 21. burning of fossil fuels or wood
- 23. Nitrogen cycle occurs with help from living ___
- 24. water vapor collects in the clouds
- 25. Bacteria and ______ can fix nitrogen for consumption
Down
- 1. rain, sleet, snow
- 2. plants make their own food
- 3. rainwater seeps through the ground
- 7. organisms break down food for energy
- 9. water cycle is driven by the _____
- 12. urine and feces converted to ammonia
- 15. water vapor leaves plants and returns to atmosphere
- 16. 97% of earth's water is in the ___
- 19. carbon's form in the atmosphere
- 22. most important living organism to break down nitrogen