Answer:
the skin on your body
Explanation:
because it is a tough cover it protects the body in many ways,thus it's water proof.
Since there are 20 heigh-associated genes and only two of the alleles are identical to both of them, the other genes could have different effects on the development of their bone and muscle cells which can result to the two women having different heights.
It converts it into electrical energy. Hope that helps :D