Across
- 2. pulmonary, aortic
- 4. cardiac muscle
- 5. sinoatrial nodes
- 7. outer layer
- 14. endothelium lines chambers
- 16. pump
- 17. graphic record of heart activity
- 18. transport vehicle
- 19. double-walled sac
- 20. receives blood
- 21. ventricles relax
Down
- 1. pumps blood out
- 3. ventricles contract
- 6. tricuspid, bicuspid
- 8. blood to/from all body tissues
- 9. anchors valve flaps in their closed positions
- 10. network of tubes
- 11. blood to/from lungs
- 12. wall between ventricles & atria
- 13. prevent backwards flow of blood
- 15. atria contract