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What do the ventricles do in the human heart?

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Illustration of a human heart cross-section showing four chambers-left and right atria and ventricles-with labeled major blood vessels. An inset highlights cardiac muscle tissue, showing myocytes and intercalated disks. — human cardiovascular system The human heart is both a pump and a muscle. Its four chambers move blood efficiently, while cardiac muscle cells joined by intercalated disks synchronize each contraction.

In the human heart, the ventricles are the two lower chambers responsible for pumping blood out of the heart and into the circulatory system. They exert the major force required to circulate blood to the lungs and the rest of the body.12

The two ventricles function as follows:

Right Ventricle: This chamber receives deoxygenated blood from the right atrium and pumps it into the pulmonary artery, which transports the blood to the lungs for oxygenation.123
Left Ventricle: This chamber receives oxygenated blood from the left atrium and forces it through the aorta to be distributed to all parts of the body. Because it must pump blood throughout the entire systemic circulation, the walls of the left ventricle are significantly thicker and more heavily muscled than those of the right ventricle.142

The ventricles are separated by the interventricular septum, and their openings are guarded by valves that ensure blood flows in the correct direction.12