Heart.rar -

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

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

Four valves (tricuspid, pulmonary, mitral, and aortic) act as one-way gates to keep blood flowing in the correct direction. ⚙️ How the "System" Works Heart.rar

The right and left atria receive incoming blood.