Across
- 4. large chambers toward the bottom of the heart
- 7. non-oxygenated blood goes through to the lungs
- 9. tissue that contracts forcefully when excited
- 10. the outer wall of the heart
- 13. these work as a pump mechanism
- 14. irregular heart beat
- 15. found at the top of the heart
Down
- 1. also known as the aortic valve
- 2. a valve leading to the left ventricle
- 3. cords known as the heart strings
- 5. the heart's own electric system
- 6. a valve leading to the right ventricle
- 8. a band of muscle under the heart
- 11. tissue with one or more layers of cells
- 12. voluntary muscle tissue