Explain the path of the electrical impulse through the heart.
The SA node generates the electrical impulse that travels through the pathways in the atrium. The atrial muscle contracts to pump blood from the atria through the valves into the ventricles. The electrical impulse then travels to the AV node. The impulse is delayed by 100ms before it reaches the bundle of his and it divisions, the right and left bundle branches. These branches break into the purkinje system, which conducts the impulse to the inner wall of the ventricles, causing the ventricles to contract and pump blood from the right ventricle to the lungs and the left ventricle to the aorta.