In the lungs, the pulmonary arteries (in blue) carry unoxygenated blood from the heart into the lungs. Throughout the body, the arteries (in red) deliver oxygenated blood and nutrients to all of the body’s tissues, and the veins (in blue) return oxygen-poor blood back to the heart.
The aorta is the large artery leaving the heart. The superior vena cava is the large vein that brings blood from the head and arms to the heart, and the inferior vena cava brings blood from the abdomen and legs into the heart.
