Across
- 4. can relax and contract
- 6. nervous system function
- 7. found in the skin, organs & muscles
- 12. carry blood away from the heart
- 13. carry blood to the heart
- 15. the function is breathing
Down
- 1. commonly called the windpipe
- 2. when contract the tricep relax
- 3. the organ that pulls air into the body
- 5. the heart muscle is called
- 8. hair, nails, and skin
- 9. muscle you use to breathe
- 10. is an involuntary organ
- 11. supports and protects
- 14. largest organ