Across
- 4. – Non-living parts of an ecosystem.
- 6. respiration – Cells use oxygen to get energy from food.
- 7. – Plants use sunlight to make food.
- 9. ecosystem – A land ecosystem.
- 11. – All the water on Earth.
- 12. – Where all living things exist.
- 14. – Cells get energy without using oxygen.
- 18. – Total weight of living things in an area.
- 19. gases – Gases that trap heat in the air.
- 21. – A chemical needed for life.
- 22. ecosystem – A water ecosystem.
Down
- 1. – The hard outer layer of Earth.
- 2. – Toxins build up in an organism over time.
- 3. level – A group based on how organisms get energy.
- 5. – The air around Earth.
- 8. effect – Earth gets warmer from trapped heat.
- 10. – Living things and their environment working together.
- 13. ecosystem – An ecosystem that stays healthy and supports life.
- 15. efficiency – Energy passed from one level to the next.
- 16. – Living parts of an ecosystem.
- 17. precipitation – Acid rain caused by polluted air.
- 20. – Too many nutrients cause too much plant growth in water.