Blood vessel prevent backflow as a result of a decrease in blood pressure as the blood passes through the circulatory system. There are various kinds of blood vessels: They are roughly grouped as "arterial" and "venous", determined by whether the blood in it is flowing "away from" (arterial) or "toward" (venous) the heart. The term "arterial blood" is nevertheless used to indicate blood high in oxygen, although the pulmonary artery carries "venous blood" and blood flowing in the pulmonary vein is rich in oxygen. This is because they are carrying the blood to and from the lungs, respectively, to be oxygenated. Blood
Axillary vein vein. It terminates at the lateral margin of the first rib, at which it becomes the subclavian vein. It is accompanied along its course by a similarly named artery, the axillary artery. Axillary vein In human anatomy, the axillary vein is a large blood vessel that conveys blood from the lateral aspect of the thorax, axilla (armpit) and upper limb toward the heart. There is one axillary vein on each side of the body. Its origin is at the lower margin of the teres major muscle and a continuation of the brachial vein. This large vein is formed by the