Across
- 2. variation of living organisms within an ecosystem
- 6. organisms within soil that break down nutrients and return them to ecosystem
- 8. element that must be "fixed" into a useable form by bacteria
- 10. balance within a healthy ecosystem
- 12. build up of toxins in food chains;effects higher trophic levels
Down
- 1. organism that hunts and eats a prey
- 3. non native organisms that can outcompete native species
- 4. gas removed from atmosphere by photosynthesis;buildup can lead to greenhouse effect
- 5. symbiotic relationship in which one organism benefits and the other is unaffected
- 7. buildup of nitrogen in an ecosystem can result in toxic algae blooms
- 9. symbiotic relationship in which a parasite harms a host
- 11. symbiotic relationship in which both organisms benefit