Our body is a constant source of mystery and even though we walk around on a daily basis not knowing certain things about ourselves, this is what makes the process of self discovery even more fun. One of the most commonly considered mysteries of the human body has to do with our veins. After all, if our blood comes out red, then why would the veins that hold the blood be blue?
As it turns out, this is a question that is much easier to answer than most might realize. The blood that runs through our bodies is always red, whether it is running through our veins or not. This is due to the fact that the skin scatters far more blue light than it does red. The fact that we see it as blue inside of the veins is an optical illusion.
In a world that is filled with various brain teasers and attempts to confuse us, it can be tough to imagine that our body is in on the act too. The skin that is located in the area of the vein is part of what contributes to this amazing illusion. Since this skin appears to be far more red than the actual vein, the mind perceives the color contrast in an interesting way.
The color contrast serves to enhance the hue of the veins. Blood, on the other hand, will always be red no matter what and this is because of the amount of iron that it contains. Once this iron is given the chance to mix with the blood in the veins, the red appearance is created. However, did you know that animal blood is different?
All of the blood in the world does not come with the same sort of chemical makeup and this is important to remember. The blood of certain animals contains far more copper than iron and this causes their blood to turn blue when it mingles with the oxygen. Most curiously of all, the blood of a leech contains an amount of iron that is less concentrated the iron in human blood and this causes their blood to take on a greenish appearance.