Across
- 3. series of events or processes that repeat regularly and usually lead back to the starting point.
- 5. A step in the water cycle where water becomes a gas
- 7. Where water is collected underground
- 9. When water vapor cools on a solid surface
- 10. A part of the nitrogen cycle where nitrates are formed and used by plants.
- 11. The stage in the carbon cycle where carbon dioxide is released by cars and factors when fossil fuels are burned.
- 12. Plants use remove carbon dioxide during this process to make glucose.
- 13. An organic element that composes all living things
Down
- 1. the cycle by which nitrogen is converted into various chemical forms
- 2. Examples include rain, sleet, snow, and hail
- 4. An excess amount of this material may pollute water sources.
- 6. The stage where ammonia is formed during the nitrogen cycle.
- 8. This gaseous form of carbon is exhaled by humans