Across
- 3. – The process plants use to make food from sunlight.
- 8. – A gas that forms a protective layer in Earth’s atmosphere.
- 9. – The breakdown of organic matter by bacteria and fungi.
- 10. – A type of plant that stores water in its thick leaves or stems.
- 12. – The time of year when day and night are equal in length.
- 13. – The land area that drains rainwater into a common outlet.
- 17. – The variety of life in a particular habitat or on Earth.
- 19. – The underground network of fungal threads.
- 20. – The upper layer of trees in a forest, forming a dense cover.
Down
- 1. – The study of Earth's landforms and the processes that shape them.
- 2. – The gradual wearing away of rock or soil by wind or water.
- 4. – A close and often long-term interaction between two species.
- 5. – A treeless biome with frozen subsoil and short growing seasons.
- 6. – A seasonal wind bringing heavy rains to certain regions.
- 7. – The transfer of pollen enabling plant reproduction.
- 11. – Permanently frozen ground found in polar regions.
- 14. – A community of living things interacting with their environment.
- 15. – The natural home or environment of an organism.
- 16. species – A species that has a disproportionately large effect on its ecosystem.
- 18. – Where a river meets the sea, mixing freshwater and saltwater.