What is Skin For? – The layers of human skin
People often ask – what is skin? Basically your skin does a lot for your body: it provides protection, it allows you to sense temperatures and textures, and it often indicates the state of your overall health. If something happens to this vital part of your body, such as a cut, rash, burn, or irritation, your overall health, comfort, and appearance can be put into jeopardy. Considering how important it is to your life, have you ever stopped to ask yourself, what is skin?
What many people do not realize is that skin is actually an organ. When you think of bodily organs, you probably imagine smaller organs, such as the heart, liver, kidneys, or lungs, but the skin is one large organ surrounding and protecting all of these smaller organs. An organ is defined as a structure of cells and tissues that perform a specific function within an organism. Under this definition, the skin certainly qualifies. This page provides information that answers the question what is skin?
The layers of the skin
The skin is made up of several layers and each skin layer performs specific functions
- Subcutaneous fat layer (subcutis)
The epidermis is what provides the layer of protection between the outside world, and the rest of your body. The epidermis is the thin outer layer of the skin which consists of the following parts:
- Stratum corneum which consists of mature keratinocytes which contain fibrous proteins (keratins). The outermost layer is continuously shed. The stratum corneum prevents the entry of most foreign substances as well as the loss of fluid from the body.
- Keratinocytes (squamous cells) layer, just beneath the stratum corneum, contains living keratinocytes (squamous cells), which mature and form the stratum corneum.
- Basal layer is the deepest layer of the epidermis, containing basal cells. Basal cells continually divide, forming new keratinocytes, replacing the old ones that are shed from the skin’s surface.
The epidermis also contains melanocytes, which are cells that produce melanin (skin pigment).
Beneath the epidermis lies the dermis, which is where more functions are performed through the help of glands, nerves, capillaries, and more.
Within the dermis, there are sweat glands, hair follicles, and nerve endings, all within a capillary bed. The sweat glands and capillaries within the dermis allow the body to perform vital cooling functions, and the capillaries also allow important nutrients to be delivered to the skin cells. The nerve endings, of course, enable us sense heat, cold, pressures, and pain.
The dermis is held together by a protein called collagen, made by fibroblasts. This layer gives skin flexibility and strength. It also contains pain and touch receptors.
The Subcutaneous layer
The subcutaneous layer is the deepest layer of skin. This skin layer consists of a network of collagen and fat cells and helps conserve the body’s heat and protects the body from injury by acting as a “shock absorber.”
So, what is skin?
Basically, the skin is an organ that acts as an all important barrier and protective force for our bodies. It enables the body to stay well balanced and regulated while interacting safely with the rest of the world.
If you have questions about the skin contact your local doctor, who will arrange for you to see a dermatologist.