Learn about the human heart anatomy, chambers, valves, blood vessels, and how it pumps blood through the circulatory system to sustain life
The heart is a muscular organ located in the thoracic cavity, slightly to the left of the midline, between the lungs. It is about the size of a fist and lies within the pericardium, a protective sac. The heart functions as the central pump of the circulatory system, ensuring a continuous flow of blood throughout the body. Externally , the heart shows four main chambers divided into two atria (upper chambers) and two ventricles (lower chambers). The atria receive blood, while the ventricles pump it out. On the surface, grooves called sulci mark the separation of chambers and contain blood vessels. Small pouch-like extensions, known as auricles, increase the capacity of the atria. Internally , the heart is divided by septa into right and left sides. The right atrium receives deoxygenated blood from the body and passes it to the right ventricle, which pumps it to the lungs through the pulmonary artery. The left atrium receives oxygenated blood from the lungs and delivers it to the...