Across
- 2. (of a species, family, or other group of animals or plants) having no living members; no longer in existence.
- 3. the envelope of gases surrounding the earth or another planet.
- 4. the branch of biology that deals with the relations of organisms to one another and to their physical surroundings.
- 6. contaminate (water, air, or a place) with harmful or poisonous substances.
- 8. the natural home or environment of an animal, plant, or other organism.
- 9. the surroundings or conditions in which a person, animal, or plant lives or operates.
Down
- 1. protect (something, especially an environmentally or culturally important place or thing) from harm or destruction.
- 2. a biological community of interacting organisms and their physical environment.
- 5. decayed organic material used as a plant fertilizer.
- 7. trash, such as paper, cans, and bottles, that is left lying in an open or public place.