Conductive Pathways

Conductive Pathway: Electrical impulses originating in the heart cause the cyclic contraction___ of the muscles.

Conductive pathway: A group of nerve cells located in the right atrium and called the sinoatrial (SA) node, or the pacemaker, sends out an electrical impulse that spreads out over the muscles in the atria. The atrial muscles then contract and push blood into the ventricles. After the electrical impulse passes through the atria, it reaches the atrioventricular (AV) node, a group of nerve cells located between the atria and ventricles. The AV node sends the electrical impulse through the bundle of His, which are nerve fibers in the septum. The bundle of His divides into a right bundle branch and a left bundle branch, which carry the impulse down through the ventricles. The bundle branches further subdivide into the Purkinje fibers, a network of nerve fibers throughout the ventricles.

1. Sinoatrial (SA) node

2. Atrioventricular node (AV)

3. Bundle of His

4. Left and right bundle branches 

5. Purkinje fibers