Which of the following is the longest vein in the body?
ExplanationVeins in the extremities can be broadly classified as either superficial or deep. The superficial veins are located between the skin and the deep fascia. In the legs, these include the great and small saphenous veins and their tributaries. The great saphenous vein is the longest vein in the body. It originates on the medial side of the foot and ascends anterior to the medial malleolus and then along the medial side of the calf and thigh, and drains into the common femoral vein. The deep veins of the leg accompany the major arteries. There are usually paired peroneal, anterior tibial, and posterior tibial veins in the calf, which converge to form the popliteal vein. The popliteal vein ascends in the thigh as the femoral vein. The confluence of the femoral vein and deep femoral vein forms the common femoral vein, which ascends in the pelvis as the external iliac and then the common iliac vein, which converges with the contralateral common iliac vein at the inferior vena cava. In the arms, the superficial veins include the basilic, cephalic, and median cubital veins and their tributaries. The deep veins of the arms accompany the major arteries and include the radial, ulnar, brachial, axillary, and subclavian veins. The subclavian vein converges with the internal jugular vein to form the brachiocephalic vein, which joins the contralateral brachiocephalic vein to form the superior vena cava. Bicuspid valves are present throughout the venous system to direct the flow of venous blood centrally.
