Across
- 2. carries blood from the body into the heart
- 3. largest blood vessel
- 5. in the veins that closes an opening so that blood flows in one direction
- 6. beat of the heart
- 9. cells need this to function
- 11. divides the right and left ventricles
- 13. small artery
- 15. this surrounds the heart
- 16. blood that is poor in oxygen
Down
- 1. the two lower chambers of the heart are called
- 4. smallest blood vessel
- 7. small vein
- 8. middle layer of the heart
- 10. is breathed out
- 12. largest vein in the body
- 14. the two upper chambers of the heart are called
- 17. largest artery