The right atrium receives oxygen-poor blood from the body and pumps it to the right ventricle through the tricuspid valve.
The right ventricle pumps the oxygen-poor blood to the lungs through the pulmonary valve.
The left atrium receives oxygen-rich blood from the lungs and pumps it to the left ventricle through the mitral valve.
The left ventricle pumps the oxygen-rich blood through the aortic valve out to the rest of the body.
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