Across
- 4. environment that is home to an organism
- 8. Restricts growth of population
- 11. the mass of living biological organisms
- 12. system of interaction of environment and organisms
- 15. organisms that make their own food
- 19. breaks down dead organic material
- 20. nonnative organisms spreading in environment
Down
- 1. living things in an ecosystem
- 2. biological variation of a species
- 3. nutrients and energy is passed between organisms
- 5. non-living things in an ecosystem
- 6. inborn impulse
- 7. 10% of energy given to levels above it
- 9. organism that doesn't make its own food
- 10. organism helps define entire ecosystem
- 13. organism kills and eats another organism
- 14. animal that is hunted or killed for food
- 16. rivalry over resources between organisms
- 17. all food chains of an ecosystem
- 18. variety of life in an ecosystem