Across
- 3. Medicine that prevents disease by building immunity
- 6. At risk of dying out completely
- 8. A group of living things that can breed together
Down
- 1. Money given to support a cause or organization
- 2. Scientific tests done to discover new information
- 4. Animals, birds, and plants in their natural state
- 5. Tests done on volunteers before a drug is approved
- 7. The natural environment where an animal lives