The pulmonary artery would show less oxygenated blood due to blood coming into the heart's right atrium to be oxygenated by the lungs after traveling into the right ventricle then into the pulmonary artery then to the lungs. The pulmonary veins bring oxygenated blood into the left atrium from the lungs, then to the left ventricle, then to the aorta out into the rest of the body, head, etc. The other arteries and veins of the body carry oxygenated and less oxygenated blood respectively.
written by Marilyn Jones
hope this helps