Across
- 3. Gas that enters the blood in lungs
- 4. Largest artery in the body.
- 5. Double-layered membrane around heart
- 10. Smallest type of blood vessel.
- 11. Relaxation phase of the heartbeat.
- 13. Innermost lining of blood vessels.
- 14. Special nervous tissue of right atrium
- 15. Muscular middle layer of the heart.
- 16. Abnormal swishing sound of the heart
Down
- 1. Small vein.
- 2. One of two lower chambers of the heart.
- 6. Small artery.
- 7. vessel carrying blood to the heart
- 8. Regulators of blood flow in the heart or vein
- 9. Contraction phase of the heartbeat
- 12. Inner lining of the heart.