Blood used by the body is brought back to the heart and lungs by the veins of the body. Once the blood has gathered more oxygen from the lungs, it is pumped back out to the body through the arteries.
Review Date 11/9/2019
Updated by: Jatin M. Vyas, MD, PhD, Assistant Professor in Medicine, Harvard Medical School; Assistant in Medicine, Division of Infectious Disease, Department of Medicine, Massachusetts General Hospital, Boston, MA. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.