Final answer:
Energy is conserved during a heartbeat as electrical signals are converted to mechanical energy to pump blood, and potential energy is stored and released in the heart muscle during the cardiac cycle.
Step-by-step explanation:
In the process of a heart beat, energy conservation follows the law of conservation of energy, which states that energy cannot be created or destroyed but can only change forms. Within the cardiac cycle, which consists of systole (contraction) and diastole (relaxation), energy is conserved as follows:
- During systole, an electrochemical signal initiates at the sinoatrial (SA) node, causing the atria to contract and pump blood into the ventricles. This action converts electrical energy into mechanical energy, which is used for the work of pumping blood.
- When the signal reaches the atrioventricular (AV) node, it causes a pause allowing the ventricles to fill completely before they contract. Upon contraction, the ventricles pump blood into the aorta and the pulmonary arteries, further converting stored elastic (potential) energy into the kinetic energy of blood flow.
- Finally, as the ventricles relax (diastole), they are filled with blood and potential energy is restored, preparing for the next cycle.
This rhythmic conversion of electrical energy to mechanical energy and the alternating storage and release of elastic energy ensures that heart muscle efficiently continues its function without losing energy, exhibiting the principles of energy conservation within biological systems.