7. Scientific explanation Arteries do carry oxygenated blood EXCEPT for PULMONARY ARTERY which carry deoxgenated blood from heart to lungs to undergoes gaseous exchange process Veins do carry deoxygenated blood EXCEPT for PULMONARY VEIN which carry oxygenated blood from lungs to heart (left atrium) It is better to remember that arteries carry blood away from the heart and veins carry blood to the heart