A natural "pacemaker" called the sinoatrial (SA) node sends electrical impulses that tell the heart muscles when to contract. 📊 Heart Rate: The Vital Metric All About Heart Rate | American Heart Association
Receives oxygen-rich blood from the lungs and pumps it out to the rest of the body. Heart.rar
Receives deoxygenated blood from the body and pumps it to the lungs. A natural "pacemaker" called the sinoatrial (SA) node