1. Heartbeat regulation

2. SA Node (AKA Pacemaker)
Sinoatrial node (SA)
Specialized bundle of myocytes
Starts the wave of heart muscle contraction
“Sets the pace”

3. AV Node Atrioventricular node (AV)
Picks up impulses from the SA node and transmits the nerve impulse to a network of fibers in the ventricles

4. Regulation of Heartbeat
Heartbeat depends on body’s need for oxygen-rich blood
Increase heart beat:
Sympathetic N.S.
Decrease heart beat:
Parasympathetic N.S.

5. Anatomy Animation Heartbeat
YouTube Video
Anatomy Animation Heartbeat

6. Regulation of the Heartbeat
YouTube Video
Regulation of the Heartbeat

7. STOP HERE!