The Human Skin: Basics

First things first, you who have taken the time to notice your skin need to know the basics, if you still don’t, that is. I’ll try not to bore you with anatomy and histology of the largest organ of the body so simply put it has 3 major parts from the outermost to the deepest: the epidermis, dermis and hypodermis (aka subcutaneous layer).

The epidermis has 5 major parts from top to bottom: stratum corneum, lucidum, granulosum, spinosum and basale. Here are some facts to get you familiarized with them:

  • The stratum corneum is the tough outermost part of our skin. They are the older cells that are pushed and piled upwards while they lose their nucleus and accumulate keratin. In the end, they become flat, thin and all that’s left is keratin; they die and are shed everyday in thousands.
  • The second layer is relatively lucent compared to the rest that’s why it is called stratum lucidum.
  • The stratum granulosum is somewhat darker in color because of the keratohyalin and lamellar granules.
  • The stratum spinosum is thick and is named as such because they look like they have spines. These are actually proteins formed into desmosomes, the cells’ way of sticking to and communicating with each other.
  • The melanin pigments hated by the dark-skinned and so much loved by the pale ones are deeper in the basale layer.

The dermis is the next layer under the epidermis.  Under the microscope, you can see it has the hair follicles, blood vessels, sweat glands, sebaceous glands, nerve endings, pressure and touch receptors, and arrector pili. Under that is the hypodermis which contains fat and blood vessels. Now that you know the basics, here are some trivia that may help you understand skin more:

  • Did you know? Lips are pink-colored because they do not have much of the corneum layer. Blood vessels  underneath show through more under the lucidum layer.
  • Arrector pili are the strips of muscle attached to the base of your hair; they are responsible for giving you goose bumps!
  • It takes about 28-30 days to grow new skin.
  • Your palm has no sebaceous glands. Only sweat glands.
  • There are certain bacteria on your skin that are harmless; in fact, they are called normal flora.
  • Darker-skinned people are more protected against UV than lighter-skinned people because of melanin.

The human skin is more than a simple barrier. If you’re ready to learn more of its functions, see the following page :)


Leave a Reply