Skin Cell Factory T e bottom of the epidermis is a skin factory. Live cells are made there. T e live cells slowly push to the top of the epidermis. T en they die. It may seem strange to shed so


many skin cells. Yet some animals shed even more skin than we do. You see, your skin stretches as you grow. A snake’s doesn’t. A snake must shed its skin all at


once. Every six weeks or so, a snake’s outer skin dies. It splits open. T e snake slithers out wearing a new skin. Frogs and salamanders shed their skins, too.


This catfi sh’s skin helps it fi nd food and avoid danger.


Keep in Touch You know some of the jobs that the epidermis does. Now here’s something that it doesn’t do. If you cut or scrape it, it won’t hurt


or bleed. It can’t. It has no nerves or blood vessels. T e next layer of skin does, though. Try touching something. You’ll


know if it feels smooth, rough, cold, or hot. Close your eyes. Now touch the bristles of a brush. You can tell if it’s a paintbrush or a toothbrush. You can thank the nerves in your dermis for your sense of touch.


Sending Signals T e dermis is loaded with nerves. T e nerves send signals to your brain. You feel sensations faster than the blink of an eye. Many animals have a greater sense


of touch than we do. Look at a catfish. It has smooth skin. T is increases its sense of touch. With its sensitive skin, a catfish


can feel movement in the water. It can sense a moving fishing line and quickly swim out of the way.


Fast Fact: You grow a new set of outer skin cells every month.


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