Which Sequence Places the Components of the Electrical Activity of the Heart

Question

Which sequence places the components of the electrical activity of the heart in the proper order?
A) AV node, Purkinje fibres, SA node
B) Purkinje fibres, AV node, SA node
C) SA node, AV node, Purkinje fibres
D) AV node, SA node, Purkinje fibres

Accepted Answer

The electrical activity of the heart starts at the SA node (sinoatrial node), which acts as the natural pacemaker. The impulse then travels to the AV node (atrioventricular node), and finally through the Purkinje fibers to cause the heart muscle to contract. This sequence ensures the coordinated contraction of the atria and ventricles.