Across
- 4. Organism that obtains food by consuming other living things; also called consumers
- 6. Series of steps in an ecosystem in which organisms transfer energy by eating and being eaten
- 7. Process used by plants and other autotrophs to capture light energy and use it to power chemical reactions that convert carbon dioxide and water into oxygen and energy-rich carbohydrates such as sugars and starches
- 8. First producer of energy-rich compounds that are later used by another organism
- 9. Organism that is able to capture energy from sunlight or chemicals and use it to produce its own food from inorganic compounds; also called a producer
- 12. Each step in a food chain or food web
- 15. Process in which chemical energy is used to produce carbohydrates
- 17. Model of the relative amounts of energy or matter contained within each trophic level in a given food chain or food web
- 19. Network of complex interactions formed by the feeding relationships among the various organisms in an ecosystem
Down
- 1. Chemical substance that an organism needs to sustain life
- 2. Process in which elements, chemical compounds, and other forms of matter are passed from one part of the biosphere to another
- 3. A natural feature (such as a landmass, forest, or ocean) that stores carbon
- 5. Process of converting nitrogen gas into nitrogen compounds that plants can absorb and use
- 10. Material made up of decaying bits of plant and animal material
- 11. Process by which bacteria convert nitrates into nitrogen gas
- 13. Single essential nutrient that limits productivity in an ecosystem
- 14. Photosynthetic algae found near the surface of the ocean
- 16. Total amount of living tissue within a given trophic level
- 18. Organism that relies on other organisms for its energy and food supply; also called a heterotroph