Across
- 2. This prevents the backflow of blood
- 3. The body's main artery
- 6. The left and right sides of the heart are separated by the _______ septum
- 9. When ventricles contract and force blood into arteries and parts of the body
- 10. A blood vessel that carries blood away from the heart
- 12. One of the two upper chambers of the heart
- 14. When ventricular muscles relax and expand
Down
- 1. Oxygenated blood from lungs enters left atrium through _________ veins
- 4. The pulmonary artery carries _________ blood from the heart to the lungs
- 5. This stimulates the cardiac muscle to contract
- 7. One of the two lower chambers of the heart
- 8. This carries oxygen and nutrients to the body's cells
- 11. A muscular pumping organ which has four chambers
- 13. A vessel that returns blood to the heart