Across
- 2. Upper chamber of the heart
- 4. Regulates the pace of the heart
- 8. Makes up more than half your blood
- 9. Fights bacteria that make you sick
- 12. The liquid that moves around in blood vessels
- 13. The smallest blood vessel in the body
- 15. Carries blood away from the heart
- 16. To breathe out
- 17. Carries blood to the heart
- 18. The smallest item in your body
Down
- 1. Things that you need to live and grow
- 3. Carries oxygen throughout the body
- 5. A pump
- 6. Makes you sick
- 7. The lower chamber of your heart
- 10. A chemical messenger
- 11. An artery or vein
- 14. Helps your blood clot