All About The Human Skin
The skin is the largest organ of the human body. It has seven layers and guards the underlying muscles, bones and other internal organs.
The thickness of the skin depends on how often the particular surface is being used. For example, the sole is the thickest in our body. The inside surface of the hand is also thick because we use our hands often.
The anatomy of the Skin.
The three layers of the skin
The skin has seven layers, But I’m going to cover only three. I am not going to go deep into the anatomy of the Skin.
The three layers of the skin that are important to us are: The epidermis, the dermis and the hypodermis- also know as the subcutaneous fat layer
The epidermis is the outermost layer of the skin. This layer consists of many special cells like Keratinocytes that make a special fat which gives skin it’s waterproof properties.
Epidermis also consists of Melanocytes, Melanin producing cells. Melanin is a pigment giving us the colour of our skin.
This layer is continuously shed and replaced, every 15–30 days.
The epidermis is sub-divided into 5 layers, which I am not going to discuss. I will leave this to the dermatologies in the making 😉
The dermis is the Skin layer beneath the epidermis. It is a thick layer made up of tough connective tissues , hair follicles, and sweat Glands.
Hypodermis/ subcutaneous layer
This is the innermost layer of the skin. It is made of fat and connective tissue. It plays an important part in controlling our skin temperature and acts as a cushion against mechanical injury.
Functions Of The Skin
The skin has several different functions:
- Protection: The skin protects us from mechanical trauma and physical injuries, variations in temperature, radiations and chemical.
- Immunity: The Skin has it’s own bacteria that defends the Body from external bacteria. The skin’s bacteria destroys the micro-organisms trying to get into the Body.
- Temperature Regulation: When it is too hot, our bodies loose excess heat through sweating. On the other hand, when it’s cold, the tiny hairs on our skins projects, allowing the hair to entrap a thick layer of “insulator air” next to the skin, so that transfer of heat to the surroundings is greatly depressed.
- Sensation: The skin has many nerve endings and receptors that sense changes. This allows us to feel everyday objects, feel pain, determine hot from cold.
- Elimination of waste products: Waste products are released from the body via the surface of the Skin regulated by the composition of the sweat.
- Vitamin D Synthesis: With the help of the suns rays, the skin produces vitamin D3. This is essential for building strong, well shaped bones.