Across
- 6. blood vessels that connect veins and arteries
- 7. fragments of cells that help blood to clot
- 9. this organ is made up of cardiac muscle
- 10. blood vessels that carry blood away from the heart
- 11. blood vessels that carry blood back to the heart
- 12. the top chambers of the heart
- 13. these blood cells carry oxygen
Down
- 1. the number of chambers in the heart
- 2. these blood cells fight off disease
- 3. flaps of skin that act like doors to keep blood fro back-flowing
- 4. the abbreviation for measuring heart rate
- 5. the bottom chambers of the heart
- 8. 90% of blood's volume