Knowledge N Fact4u

Why do my fingers absorb water and become wrinkled? •Human finger tips do not become wrinkled, because they absorb water.  •Skin is a fairly good barrier that keeps out most of the external water. •If our fingers did absorb a significant amount of water after staying in the pool or bath for several minutes, then our fingers would swell to round, plump shapes, which is the opposite of wrinkling.  •The wrinkling is actually caused by a reduction of fluid inside the finger tips. •How can our finger tips experience reduced fluid internally when exposed to increased fluid externally? •From a physical perspective, this effect seems to be a paradox. The answer is that the wrinkling of wet finger tips is an active biological response, rather than a passive physical effect. •Scientists have known for almost a hundred years that nerve damage in the hand can result in a person no longer being able to get wet-induced finger wrinkles. Finger wrinkling is therefore controlled by