What does skin do?
Skin performs many different roles. These include sensation, protection, temperature regulation, excretion and production of vitamin D.
Sensation
Your skin has many receptors (sensors) that perceive sensations such as touch, temperature changes, pressure and pain.
Protection
Skin is an elastic covering. It protects you against exposure to dangerous things in the environment such as bacteria. It also repels water, minimises water loss from the body and protects underlying structures such as blood vessels, nerves and organs.
Temperature regulation
Your skin helps you maintain a healthy body temperature in two ways:
- by changing the diameter of your blood vessels in your dermis
- to cool your body, blood vessels in the skin enlarge in diameter so that heat is lost through the skin
- when warmth is required, the blood vessel diameters become smaller and heat is conserved
- by perspiration (sweat glands cause water to be evaporated from the surface of your skin, cooling your body).
Excretion
Your body excretes substances through the skin:
- sebum (skin oil), which helps to make your skin water repellent and maintain its smooth texture, and also defends your body against fungus and bacteria
- water, salts and several other substances, through the process of perspiration.
Vitamin D
Vitamin D is formed inside your body but first it has to be activated by your skin, which needs to be exposed to ultraviolet light from the sun.
