Learn About Types of Skin
Animal skin is pretty amazing. So is yours! Let's take a look at what's under your skin and its three layers:
This top layer guards against harm from outside. Dead skin cells are pushed up to the surface as new, living cells grow in below. This layer is often covered with hair (in mammals), scales (in reptiles and fish), or feathers (in birds).
Below the epidermis lies this thicker layer with lots of important structures inside. The dermis holds blood vessels that carry blood through your skin as it travels to and from the heart. It's also full of nerves. These send signals to your brain each time you touch something. Just one square inch of average skin has over 1000 nerve endings! Sweat glands are tube-shaped structures that make sweat and carry it to the skin's surface. This helps cool you off.
Hairs grow from tube-shaped hair follicles in the dermis. Next to each hair follicle is a sebaceous (sih-BAY-shus) or oil gland. It produces an oily liquid which travels up the hair. It helps to keep your skin soft. Also attached to the hair follicle is the hair erector muscle. When you get cold (and sometimes at other times), it tugs at the hair. This makes it stand up and form a "goosebump" on your skin. What's the point of standing hair? Back millions of years ago, humans had a lot of hair. And when that hair stood on end, it kept more heat closer to the skin—like extra insulation. These days, humans don't have enough hair for this to work. But goosebumps still persist, as a leftover from those hairy olden days!
SUBCUTANEOUS (sub-kew-TAY-nee-us) or Fatty Layer.
This layer of padding helps keep your body warm and acts as a "shock absorber" to protect what's under it.
As you can see, your super-sensational skin is always working hard for you. So don't forget to say thanks!