Across
- 5. the air surrounding Earth; made up of 78% nitrogen, 21 % oxygen, and .03% carbon dioxide
- 7. the process that takes place when a liquid changes to a gas
- 8. a model explaining how carbon molecules move between the living and nonliving world
- 9. the process that takes place when a gas changes to a liquid
- 10. the height above the ground or other surface, such as sea level
- 12. the process in which producers make energy-rich nutrient molecules from chemicals
- 13. a mixture of mineral and rock particles, remains of dead things, air, and water that forms the topmost layer of Earth's crust and supports plant growth
- 14. in plants, the process used to produce energy for plant growth; plants use sugars produced during photosynthesis plus oxygen, or use nutrients from soil, to form energy
- 16. a series of organisms that are interrelated in their feeding habits--the smallest organism is fed upon by a larger one, which in turn is fed upon an even larger one, etc.
Down
- 1. the process by which green plants and some other organisms use sunlight to synthesize foods from carbon dioxide and water
- 2. a model that shows the amount of energy available at each feeding level in an ecosystem
- 3. the average weather conditions of an area over time, including wind, temperature and rainfall or other types of precipitation such as sleet or snow
- 4. a model explaining how water moves from Earth's surface to the atmosphere and back to the surface through evaporation, condensation, and precipitation
- 6. the process in which some types of bacteria in the soil change nitrogen gas into a form of nitrogen that plants can use
- 11. a model that shows the complex feeding relationships among organisms in a community
- 15. the distance of a place, north or south of the equator, usually expressed in degrees and minutes