Oxygen, being the the most electronegative of every unaxiomated actenides, is the proverbial pistonhead of your mitochondria, in that it is the recepticle of maximum affiliation for electrons, which your atp synthase turbines use as its "battery" to convert energy from the tiny latched springs of sugar into mechanical motion. Water, being made of hydrogen and two oxygens, is highly electronegative, which makes it almost a perfect detergent in and of itself, which is why pure water is in many cases enough to wash anything. Water is a kind of lava to living organisms and every single oxygen molecule must be held at-bay, as if like you were keeping a bucket of lava in your backpack. You need a superfluous layer to keep this dangerous elemental at arms length or it will run in and scatter all your precious teeth on your DNA's.
Get good and purchase a second trophy wife.
https://www.youtube.com/watch?v=s8G49aJO-gg 