Correction from the previous post

I made a mistake in the last post that I'd like to correct. I had written, "You might reason that the color change and transition from veins to arteries would occur in the body at the lungs, the organs of oxygen exchange, but this actually happens at the heart." I meant to emphasize how the heart is the focus of particular attention in bodily function but I did so inaccurately. The color change most certainly does occur at the lungs. Veins carry blood to the heart and arteries carry blood from the heart. The rule that veins are blue (deoxygenated blood) and arteries red have exceptions with regard to the pulmonary vein and pulmonary artery, which have the opposite. These carry blood back and forth between the heart and lungs. Thanks John, for pointing this out and correcting me.