Dermis=Lots of Blood Vessels

Your dermis is also full of tiny blood vessels. These keep your skin cells healthy by bringing them the oxygen and nutrients they need and by taking away waste. These blood vessels are hard to see in kids, but you might get a better look if you check out your grandparents' skin. As the dermis gets older, it gets thinner and easier to see through.

The dermis is home to the oil glands, too. These are also called sebaceous (say: sih-bay-shus) glands, and they are always producing sebum (say: see-bum). Sebum is your skin's own natural oil. It rises to the surface of your epidermis to keep your skin lubricated and protected. It also makes your skin waterproof — as long as sebum's on the scene, your skin won't absorb water and get soggy.You also have sweat glands on your epidermis. Even though you can't feel it, you actually sweat a tiny bit all the time. The sweat comes up through pores (say: pors), tiny holes in the skin that allow it to escape. When the sebum meets the sweat, they form a protective film that's a bit sticky.

An easy way to see this film in action is to pick up a pin with your fingers. Then wash your hands well with soap and water and dry them off completely. Now try to pick up that pin again. It won't be so easy because your sticky layer is gone! Don't worry — it will be back soon, as your sebaceous and sweat glands create more sticky stuff.
The Third Layer Is Subcutaneous Fat

The third and bottom layer of the skin is called the subcutaneous (say: sub-kyoo-tay-nee-us) layer. It is made mostly of fat and helps your body stay warm and absorb shocks, like if you bang into something or fall down. The subcutaneous layer also helps hold your skin to all the tissues underneath it.

This layer is where you'll find the start of hair, too. Each hair on your body grows out of a tiny tube in the skin called a follicle (say: fah-lih-kul). Every follicle has its roots way down in the subcutaneous layer and continues up through the dermis.

You have hair follicles all over your body, except on your lips, the palms of your hands, and the soles of your feet. And you have more hair follicles in some places than in others — there are more than 100,000 follicles on your head alone!

Your hair follicles rely on your sebaceous glands to bring on the shine. Connected to each follicle in the dermis layer is a tiny sebaceous gland that releases sebum onto the hair. This lightly coats the hair with oil, giving it some shine and a little waterproofing.


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