Ecology

2. the place where an organism usually lives
7. trees that lose all of their leaves in the fall and regrow them each spring
12. living components of the ecosystem
13. a relationship where one organism benefits while the other organism is not affected
18. the specific role of a species within its environment
19. any natural resource that can replenish itself naturally over time
21. the process of one community replacing another community that has been partially or completely destroyed
22. the coniferous evergreen forests of subarctic lands, covering vast areas of northern North America and Eurasia.
23. a community of organisms and their abiotic environment
24. the introduction of harmful substances or products into the environment
25. a close, long-term relationship between two organisms

1. an organism that is able to make its own food
3. non-living components of the ecosystem; physical and chemical characteristics of the environment
4. the study of the interactions between organisms and other living and nonliving components in their environment
5. any natural resource from the Earth that exists in limited supply and cannot be replaced if it is used up
6. a group of organisms that belong to the same species and live in a particular place at the same time
8. a species at risk of extinction because of human activity, changes in climate, changes in predator-prey ratios, etc
9. the development of a community in an area that has never supported life
10. an organism that lives by breaking down organic matter from dead organisms
11. one of the vast, nearly level, treeless plains of the arctic regions of Europe, Asia, and North America.
14. a relationship in which both organisms benefit
15. tropical or temperate grasslands that have scattered deciduous trees and shrubs
16. the part of earth where life exists; includes all living organisms on earth
17. an organism, usually an animal, that feeds on plants or other animals.
20. a relationship where one organism is harmed and the other organism benefits