Across
- 3. Nares, paired external openings
- 9. second chamber of the heart
- 10. Sends signals between body parts
- 11. System that provides movement
- 12. "Voice box"
- 15. circulates blood carrying oxygen
- 17. Removal of waste from homeostasis
- 19. Largest portion of muscle
Down
- 1. Each animal has one
- 2. long fiber like structures
- 4. Long bundle of nervous tissue
- 5. Firm tissue that isn't as hard as bone
- 6. Controls movement of internal organs
- 7. Uses oxygen gets rid of carbon dioxide
- 8. Support and protection (vertebrae)
- 9. first chamber of the heart
- 13. Relatively thin and flat protects organs
- 14. Often as big around as they are long
- 16. Each animal has two
- 18. Makes up the heart