Veins in the extremities carry blood to the heart and lungs, where the blood is oxygenated. As the blood returns to the heart from the lungs, the arteries carry the oxygen-rich blood out to the body.
David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M. Health Solutions, Ebix, Inc.