While the thoracic aorta descends through the thoracic cavity to the diaphragm, it is a continuation of the aortic arch. Branches are given off by this large vessel to the organs and muscles of the thoracic region. The anterior intercostal arteries which provide blood to the intercostal muscles, and the phrenic arteries which provide the diaphragm are contained by these branches.
The segment of the aorta between the diaphragm and the level of the fourth lumbar vertebra is the abdominal aorta. Among the main arteries, the celiac trunk is arising from the abdominal aorta. Just below the diaphragm, this very large unpaired vessel arises anteriorly. There are 3 arteries separated by it, going to the stomach is the left gastric artery; going to the spleen is the splenic artery; and going to the liver is the hepatic artery. Arising anteriorly, the superior mesenteric artery is another unpaired vessel that just below the celiac trunk. Blood is provided by it to the ascending colon, the small intestine, the appendix, the cecum, and the transverse colon.
The paired renal arteries is the next main vessels arising from the abdominal aorta. It bring blood to the kidneys. Arising from the abdominal aorta, the gonadal arteries are small paired vessels which just below the renal arteries. These are called the ovarian arteries in the female, and are called the testicular arteries in the male.