Ecology

2. forest trees that lose all of their leaves in the fall and regrow them each spring
4. the study of the interactions between organisms and other living and nonliving components in their environment
5. a relationship in which both organisms benefit
8. a relationship where one organism is harmed and the other organism benefits
10. the development of a community in an area that has never supported life
12. the introduction of harmful substances or products into the environment
14. a community of organisms and their abiotic environment
16. an organism that lives by breaking down organic matter from dead organisms
17. a relationship where one organism benefits while the other organism is not affected
20. living components of the ecosystem

1. the process of one community replacing another community that has been partially or completely destroyed
3. a close, long-term relationship between two organisms
6. a group of organisms that belong to the same species and live in a particular place at the same time
7. the place where an organism usually lives
9. the part of earth where life exists; includes all living organisms on earth
11. tropical or temperate grasslands that have scattered deciduous trees and shrubs
13. an organism that is able to make its own food
15. one of the vast, nearly level, treeless plains of the arctic regions of Europe, Asia, and North America.
18. the specific role of a species within its environment
19. non-living components of the ecosystem; physical and chemical characteristics of the environment