Complex sentence: The sole contains the thickest layers of skin on the body due to the weight that is continually placed on it; the sole is crossed by a set of creases that form during the early stages of embryonic development.
Split into simpler sentences: The sole contains the thickest layers of skin on the body due to the weight that is continually placed on it. It is crossed by a set of creases that form during the early stages of embryonic development.