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
Jugular vein resolution, or coup-de-grace. An alternate explanation for the phrase suggests "to go for the jugular" merely means to attack without restraint. The jugular vein system is essential but not particularly weak or vulnerable, because this venous system is generally found fairly deep in the body. Jugular vein The jugular veins are veins that take deoxygenated blood from the head back to the heart via the superior vena cava. There are two sets of jugular veins: external and internal. The left and right external jugular veins drain into the subclavian veins. The internal jugular veins join with the subclavian veins more