The Anatomy of the Skin

Skin is the largest organ in the body by reason of its size. It is also a very senstive organ. And skin is a protective sheath for most organs as well, by covering them and shielding them from most elements of nature like heat, or cold, and atmospheric pollutants. Skin helps in retaining body fluids and in excreting excess water. Skin has its own devices for keeping the body warm by shivering when it is cold, and sweating when it is hot.

Skin is made up of a variety of tissues, which in turn is made up of different types of cells. We typically interact with only the surface layer of the skin. This skin layer covers the entire body, reacts to heat or cold or dust, and might develop pimples or wrinkles, and may shine or sag. However, much of the working of this surface layer of the skin is connected to the health of the layers beneath it as well.

Skin has got three different layers. The outermost layer is known as epidermis, the layer next to it is dermis, and the innermost is hypodermis or subcutis. Each layers of the skin has its own functions.

Epidermis

Epidermis is the outermost layer of the skin, the one that we see and refer to by the name skin. This epidermis itself is made up of 3 different layers. The uppermost layer of the epidermis is constantly lost as dead cells, but these are continuously replenished as well. The bottom layer of the epidermis generates fresh cells that go to replace the ones of the uppermost layer that is being lost.

The epidermis portion of the skin is the effective fence that keeps out extraneous matters. It is made up of connective tissue of differing thickness. The connective tissue of the epidermis of the face is much thinner than that of the feet. The dark pigment of the skin melanin, that colors the skin, protects it from sunrays, and effects skin tanning when exposed to sun, is also in this layer. Epidermis is the skin layer where countless minute openings and hair shafts are situated.

Dermis

The next layer of the skin is known as dermis. This layer is mainly made up of connective tissue and nestles between the outer epidermis, and the innermost hypodermis. Much of the skin activity goes on in this layer since the layer is richly supplied with blood vessels, nerves, hair follicles, lymph vessels, collagen, sweat glands etc. The property of the skin as a sense organ is mainly because of the nerve tissue here.

Goose bumps that human being develop in response to cold or fear results from the activity of the muscle tissue of this skin layer. This works as a second layer skin protection after the epidermis, and can ward off the bacteria that have managed to get across the epidermis.

Hypodermis or subcutis layer

Hypodermis is the innermost layer of the skin. Regulation of body temperature is affected by this layer. This skin layer insulates the body by the presence of collagen and fat in it. This layer has got shock absorber properties as well, thereby cushioning the effects of external injuries. This skin layer is the home of the adipose tissue, which are fat deposits. These keeps the body warm, but weight watchers are terrified of adipose.