And so that's exactly why they eventually lose their nuclei and the organelles and they die. They become nothing but bundles of keratin. And carotene is very important in not only giving our skin its strength, but also making the skin impermeable to water. In fact, this entire upper layer of the epidermis, which consists of about 20 to 30 layers of dead cells, consists of nothing but cells that contain carotene. No nuclei, no organelles, only our carotene. And this makes our skin impermeable to water.