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Why does the left side of the heart pump blood to the body?

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Silhouette diagram of the human body highlighting the heart and major blood vessels, with labeled arteries in red and veins in blue to show the structure of the cardiovascular system. — Circulatory system Human circulatory system.

The left side of the heart pumps blood to the body as part of the systemic circulation circuit.12

After receiving oxygenated blood from the lungs via the pulmonary veins, the left atrium passes this blood into the left ventricle. The left ventricle then contracts to force the oxygen-rich blood into the aorta, which distributes it to tissues throughout the body.324

This process is essential because the body requires a constant supply of oxygen and nutrients to sustain its metabolic demands. To accomplish this, the left ventricle possesses a significantly thicker muscular wall than the right ventricle. This structural adaptation is necessary to generate the high pressure required to pump blood against the resistance of the extensive systemic circulation network, ensuring that blood reaches all parts of the body except the lungs.5236