Your own skin

Our Skin


The skin is the largest organ in the body. As part of the Integumentary Ssystem, skin is a strong, waterproof, ever-changing organ that contains many specialized cells and structures. Our skin weighs approximately 7 pounds and accounts for about 15% of our body weight.

The skin functions as a protective barrier from the outside elements. It also maintains the proper temperature for the body to function well. It gathers sensory information from the environment, and plays an active role in the immune system, protecting us from disease. Its most amazing feature is its ability to heal itself.

To have an idea of how complex this organ is, let me tell you that in every inch of skin there are approximately millions of cells, 650 sweat glands, 100 oil glands, 15 feet of blood vessels, 12 feet of nerves, 65 hairs, 1,300 nerve endings, and 60,000 melanocytes.
In general, there are six functions of the skin: protection, sensation, heat regulation, excretion, secretion, and absorption.

Protection
Skin has many ways to protect us from injuries and invasions:
*Melanin protects us from the sun.
*It can restore itself when it is injured by increasing the production of cells.
*Sebum serves as a barrier from external factors.
*The outermost layer of skin traps water in the body.

Sensation
Sensory nerve endings (which are more abundant on the fingertips) send messages to the brain as a defense mechanism or as a positive stimulation. They respond to temperature, pressure, touch, and pain.

Heat Regulation
Our internal thermostat is set at 98.6 F. When our body temperature increases, our skin adjusts to cool the body by evaporation through the sweat glands while our blood vessels dilate. When our body temperature decreases, we warm our bodies by constricting the blood vessels and decreasing blood flow.

Excretion
The sweat glands detoxify the body by excreting salt and chemicals through perspiration.

Secretion
Sebum lubricates and protects the skin and hair. It keeps the skin soft and protected from the outside elements. It slows down the water evaporation (the skin is 50% - 70% water), thereby maintaining the water levels in the cells.

Absorption
Our skin absorbs topical substances through the hair follicles and sebaceous glands.