The Circulatory System: The Heart

3. hold things together
5. atria are separated by the _______
7. _______ connect each atrium to corresponding ventricle
8. the medial cavity of the thorax
11. type of semilunar valve
14. the outermost layer of the pericardium
17. _______ keep the blood going in the correct direction
19. inner layer of serous pericardium, outermost layer of heart wall
21. ventricles are separated by _______
23. pumping chambers
25. delivers blood to the right atrium draining from the myocardium
26. outer layer of the serous pericardium
27. connect ventricles and arteries that stem from them and prevent blood that is leaving from flowing back into ventricle
28. delivers blood to the right atrium from upper parts of body
30. passage of the oxygenated blood from the left ventricle through the body, providing oxygen and nutrients, and back to the right atrium
32. dense connective tissue that protects the heart
33. type of semilunar valve

1. junctions between the cells are called _______
2. the layers surrounding the heart chanbers
4. makes up most of heart, mainly consisting of cardiac muscle
6. passage of the blood from the right ventricle through the lungs and back to the left atrium
9. dense network of connective tissue fiber that provides structural support and insulates electrical activity
10. layer of endothelium that lines the heart chambers
12. second layer of the pericardium
13. allow for ions to pass through
15. heart's own type of muscle, short and fat, one or two nuclei each, branched and interlocked with each other
16. muscular organ that pumps blood through the circulatory system
18. left AV valve, two flaps
20. delivers blood to the right atrium from lower parts of body
22. receiving chambers
24. cardiac and skeletal muscle are _______
29. largest artery in the body
31. right AV valve, three flaps