The path of a blood cell through the human heart begins in the right atrium, where it receives deoxygenated blood from the body via the superior and inferior vena cavae. From the right atrium, blood passes through the tricuspid valve into the right ventricle. It is then pumped through the pulmonary valve into the pulmonary arteries towards the lungs for oxygenation. Oxygenated blood returns via the pulmonary veins to the left atrium, moves through the mitral valve into the left ventricle, and is finally pumped out through the aorta to the rest of the body.