Section 10
Circulatory Routes
By Boundless
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The aorta is the largest artery in the body and is divided into 3 parts: the ascending aorta, arch of the aorta, and descending aorta.
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The ascending aorta is the first portion of the aorta; it includes the aortic sinuses, the bulb of the aorta, and the sinotubular junction.
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The arch of the aorta follows the ascending aorta and begins at the level of the second sternocostal articulation of the right side.
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The thoracic aorta is the section of the aorta that travels through the thoracic cavity to carry blood to the head, neck, thorax and arms.
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The abdominal aorta is the largest artery in the abdominal cavity and supplies blood to most of the abdominal organs.
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The abdominal aorta divides into the major arteries of the leg: the femoral, popliteal, tibial, dorsal foot, plantar, and fibular arteries.
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Veins are blood vessels that carry blood towards the heart, have thin, inelastic walls, and contain numerous valves.
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In the head and neck, blood circulates from the upper systemic loop, which originates at the aortic arch.
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The veins of the upper extremity are divided into superficial and deep veins, indicating their relative depths from the skin.
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The veins of the thorax drain deoxygenated blood from the thorax region for return to the heart.
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The major veins of the abdomen and pelvis return deoxygenated blood from the abdomen and pelvis to the heart.
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The deep veins of the lower extremity have valves for unidirectional flow and accompany the arteries and their branches.