Natural Cycles
Across
- 4. the process that releases nitrogen from the soil back into the atmosphere
- 6. a plant that hosts nitrogen-fixing bacteria
- 8. the basic building block of matter
- 9. precipitation that flows over the surface of the soil
- 11. the process in cells by which oxygen and glucose are used to produce energy and carbon dioxide
- 13. two or more atoms joined together
- 15. the process by which precipitation is gathered into a body of water
- 16. the change of a gas into a liquid
- 18. meaning earth
- 19. the cycling of chemical elements through the living and nonliving parts of an ecosystem
- 20. the conversion of nitrogen in the atmosphere to a form that can be used by plants
- 21. evaporation of excess water from a plant
- 22. the precipitation that is more acidic than normal rainwater
Down
- 1. a source of energy formed from dead plants and animals
- 2. the brown smog produced when air pollutants react with sunlight
- 3. the process that allows green plants to make sugars from sunlight, water, and carbon dioxide
- 5. a swelling on a plant root that contains nitrogen-fixing bacteria
- 7. the change of a liquid into a gas
- 10. meaning life
- 12. a pollutant released into the atmosphere
- 14. a substance that is made of only one type of atom and cannot be broken down
- 17. a molecule that consists of two or more different elements
- 23. a form of water that falls from the atmosphere