The intrinsic ability of cardiac muscle to generate action potentials (APS) rhythmically is achieved by the normal pace maker the sino atrial node (S. A node). The SA node is part of the special excitatory and conductive system of cardiac muscle. With the help of a diagram, describe this conductive system how the AP spreads throughout the muscle.
Here is a diagram that illustrates the cardiac excitation and conduction system, showing how the action potential spreads throughout the muscle:
_________________
| |
| Sinoatrial |
| Node |
| (SA Node) |
|_______¦________|
↑
|
|
|
↓
(Internodal
pathways in the atria)
↓
______________
| |
| Atrioventricular |
| Node (AV Node) |
|________________|
↑
|
|
______________________
| |
| Bundle of |
| His |
|____________________|
→
___________________
| |
| Bundle |
| Branches (Purkinje |
| Fibers) |
|_________________|
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