Heart.rar -

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

The heart is a fist-sized muscular organ located in the center of your chest, slightly behind and to the left of the breastbone. It is divided into four main chambers: Heart.rar

Your heart functions as a dual-pump system that never stops, beating approximately : A natural "pacemaker" called the sinoatrial (SA) node

Receives oxygen-rich blood from the lungs and pumps it out to the rest of the body. Heart.rar

The right and left ventricles pump blood out of the heart.

Receives deoxygenated blood from the body and pumps it to the lungs.