Chapter 3

2. A species no longer found on earth
3. may become threatened or endangered because of a combination of factors
6. A volcanic eruption is an example of this
9. Introduced species with growing populations that spread and have a negative effect on their environment
10. harmful contaminants released into the environment
11. The number of species in an area
15. The variety of life found in an area
16. Certain minerals particularly one is able to do this.

1. a species that no longer exists in a specific area
4. Acids move through the water cycle, sometimes over long distances, before returning to earth in this form
5. A forest fire is an example of this
7. The process of establishing and replacing a community following a disturbance
8. a species facing imminent extirpation or extinction
12. Taking responsibility for managing and protecting the environment
13. on a large scale, most natural ecosystems are in this state
14. species are likely to become endangered if current trends and conditions continue