Random thought

So I was pondering the meaning of life and such this morning on my way to class, and had this thought. Blood is the only bodily fluid that one can't control with one's own thoughts or muscles. You have to actually touch the bleeding area externally in order to make yourself stop bleeding. We can 'hold it in' when we have to go to the bathroom, sniffle our noses, suppress our tears, slurp up our drool, etc., but we can't will ourselves to stop bleeding. I wonder if it's significant that the thing that makes us "mortal" is not controllable by our mind or spirit?