What is skin?
Skin is the body’s largest organ. It serves as a flexible 3-layered armor to keep harmful microbes, chemicals, sunlight and other dangers at bay.
- Layer – Epidermis
The outer layer that you can touch, is the epidermis. It provides a moisture-holding barrier against germs and psychical dangers. The epidermis is constantly renewing itself by shedding dead skin cells from the surface, to make room for new ones. It is also responsible for sending nerve-signals to the brain about the environment that you are in.
Hair grows out of small pores on the epidermis. Most pores have hair so small that you can’t see them.
At the bottom of each hair sits a gland. Some produce sweat to cool the skin down and to get rid of bacteria from within the cell. Some glands pump out sebum that forms a protective barrier to hold in moisture, and to lock out disease-causing microbes.
Melanin and vitamin D
In the epidermis we also find melanin. High amounts of melanin gives the skin a darker color, making the skin great at protecting itself from the sun. Darker skin will however also need more sun exposure to make the needed amount of vitamin D. Low amounts of melanin gives the skin a fair color, making the skin more prone to sunburns. But the lack of melanin makes it easier for the skin to absorb vitamin D, with the limited sunlight that is usually available at northern latitudes.
- Layer – Dermis
Underneath the epidermis is the dermis, that contains blood vessels that feeds the skin cells and keeps them warm. It is also here in the dermis that we find the root of the hairs and the tiny muscles that tightens when we’re scared or cold.
Underneath the dermis is the subcutis. It stores reserves of fat that act as a cushion to help protect muscles and bones from bumps and falls.