Final answer:
Autorhythmicity is the heart's ability to generate its own electrical impulse, primarily initiated by the sinoatrial node, which then travels through the heart's conduction system, causing the heart to contract and pump blood. The sequence involves the SA node, AV node, Bundle of His, and Purkinje fibers, and can be recorded via an ECG.
Step-by-step explanation:
The concept of autorhythmicity refers to the heart's ability to initiate its own electrical impulse, which in turn triggers the heart to beat. The source of this impulse is the sinoatrial (SA) node, which is often referred to as the heart's natural pacemaker because it sets the rhythm of the beat. The SA node generates an electrical signal causing the atria to contract. This signal then travels to the atrioventricular (AV) node, where there is a brief delay allowing the atria to empty fully into the ventricles. After this pause, the signal continues to the Bundle of His, through the left and right bundle branches, and finally to the Purkinje fibers, which then stimulate the ventricles to contract, completing the heartbeat cycle.
The contraction phase of the heartbeat is known as systole, and the relaxation phase, when the heart fills with blood, is known as diastole. The coordinated effort of these components of the cardiac conduction system ensures that the heart works efficiently to pump blood throughout the body. An electrocardiogram (ECG) can measure and record these electrical impulses to assess the heart’s function.