Across
- 1. Region that initiates each contraction
- 2. Blood vessels that take away blood from the heart that has not yet reached a capillary
- 4. The route on the left side of the heart
- 5. Blood vessel that collects blood from the capillaries and returns it to the heart
- 7. Heart can contract by itself, without the stimulation of a nerve
- 10. The side of the heart on which the wall is thicker
Down
- 1. The route on the right side of the heart
- 3. Valve which separates the atria and ventricles
- 6. Largest artery in the body;distributes oxygenated blood to all parts of the body
- 7. Messages are carried from the _________ to the pacemaker
- 8. Another term for adrenaline
- 9. Signals the pacemaker to increase the beating of the heart