Veins and arteries are often drawn in diagrams as blue or red to show whether they have lower or higher concentrations of oxygen, but that's just how it is used in most diagrams. It doesn't mean the blood, or the veins, or arteries are actually that color
Veins and arteries are often drawn in diagrams as blue or red to show whether they have lower or higher concentrations of oxygen, but that's just how it is used in most diagrams. It doesn't mean the blood, or the veins, or arteries are actually that color