Across
- 4. The tunica consists of smooth muscle and elastic fibers that narrow or widen, causing blood pressure to increase or decrease
- 8. Vein that receives venous blood from the arms via the axillary vein and from the skin and muscles of the head via the external jugular vein
- 10. Valves that lie between the atrial and ventricular chambers on each side, and prevent backflow into the atria when the ventricles contract
- 12. The septum that divides the heart longitudinally
- 15. An artery that is a branch of the ascending aorta
- 16. The innermost layer of the heart and is a thin, glistening sheet of endothelium hat lines the heart chambers
- 17. Although cardiac muscles can beat independently, the muscle cells in the different areas of the heart have different rhythm
- 18. The visceral and outermost layer is actually a part of the heart wall
- 19. The pressure in the arteries at the peak of ventricular contraction
Down
- 1. Heart contraction
- 2. The right AV valve and has three flaps
- 3. The outermost tunic composed largely of fibrous connective tissue, and its function is basically to support and protect the vessels
- 5. A superficial vein that drains the medial aspect of the arm and empties into the brachial vein proximally
- 6. The outermost layer of the heart that encloses the heart in a double-walled sac
- 7. Valve that closes when the ventricle is full
- 9. A single vein that drains the thorax and enters the superior vena cava just before it joins the heart
- 11. Narrowing of the blood vessels
- 13. Several pairs of arteries serving the heavy muscles of the abdomen and trunk walls
- 14. Thick bundles of cardiac muscle twisted and whirled into ringlike arrangements
- 18. This contraction effectively ejects blood superiorly into the large arteries leaving the heart