Answer
Pulmonary veins carry blood from the lungs, whereas the venae cavae carries blood to the heart from elsewhere in the body.
Work Step by Step
The capillary beds in the lungs, from which the pulmonary veins draw, are the original source of oxygenated blood into the circulatory system. Other capillary beds distribute oxygenated blood into tissues, bringing back less oxygen rich blood through the venae cavae.
