The aorta is the main and largest artery in the body, leading oxygenated blood out of the heart to the rest of the body. It can be divided into four sections: the ascending aorta that branch off to the coronary arteries, the aortic arch that curves over the heart, the thoracic aorta that travels down through the chest, and the abdominal aorta that splits into the lower iliac arteries. The aorta is a good source of primary smooth muscle cells and endothelial cells.