Pulmonary vein three and five in the healthy population. The two left lobar veins may be united as a single pulmonary vein in about 25% of people; the two right veins may be united in about 3%. The pulmonary veins play an essential role in respiration, by receiving blood that has been oxygenated in the alveoli and returning it to the left atrium. As part of the pulmonary circulation they carry oxygenated blood back to the heart, as opposed to the veins of the systemic circulation which carry deoxygenated blood. A rare genetic defect of the pulmonary veins can cause them to
Experiments in the Revival of Organisms is shown being isolated from a body; four tubes connected are then connected to the organ. Using an apparatus, the heart beats in the same manner as if it were in a living organism. The film then shows a lung in a tray, which is operated by bellows that oxygenate the blood. Following the lung scene, the audience is then shown a heart-lung machine, composed of a pair of diaphragm linear pumps, venous and arterial, exchanging oxygen with a water reservoir. It is then seen supplying a canine head with oxygenated blood. The head is presented with external stimuli, which