Across
- 6. the type of circulatory system mammals have
- 9. transport blood back to the body
- 11. inner layer of the heart wall
- 13. transport blood back to the heart
- 14. outer layer of the heart wall
Down
- 1. two pumping chambers with thick walls
- 2. left AV valve
- 3. the four sections of the heart
- 4. middle layer of the heart wall
- 5. separates the two sides of the heart
- 7. tough membrane around the heart
- 8. Pointed end of the heart
- 9. two receiving chambers with thin walls
- 10. valve right AV valve
- 12. pumps blood through body