Parts of the Skin
Our skin is a complex engineered covering.
The skin has a slightly acidic coating of oil at the surface. This coating protects the skin against some bacteria. Below the surface is a complex of sweat and oil glands, hair follicles, blood vessels, nerves, and muscle tissue. These are held together by a tough connective tissue called collagen.
Collagen is very important in determining the health of the skin. The relative health of the collagen determines the contour of the skin, how wrinkled and lined it is. Healthy collagen is often called soluble collagen, because it can absorb and hold moisture.
Below the collagen is a layer of fat and muscle, which provides some contour and acts as a cushion and as insulation.
The skin has three layers. The inner most layer is known as the lower dermis, the middle layer is called the dermis, and the outer layer is known as the epidermis.
The various glands such as the oil and sweat glands originate in the lower dermis. From here, they rise to the surface of the skin to eliminate waste matter. Lower dermis also acts as a cushion for the rest of the skin. It contains the finely distributed muscles of the skin which regulate body temperature.
The dermis is the layer that lies underneath the epidermis, and it is composed entirely of living cells. It consists of bundles of tough fibers which give your skin its elasticity, firmness and strength. There are also blood vessels, which feed vital nutrients to these areas.
The most important function of dermis is respiration. The countless tiny blood vessels, or capillaries end here in finely-drawn networks, from where they feed the outer skin layer. Dermis also determines the tone of the skin.
This is the top layer of skin and the one you can actually see. It protects your body from invasion and infection and helps to seal in moisture. It's built up of several layers of living cells which are then topped by sheets of dead cells. It's constantly growing, with new cells being produced at its base. They quickly die, and are pushed up to the surface by the arrival of new ones, These dead cells eventually flake away, which means that every new layer of skin is another chance to have a soft, glowing complexion.
The lower levels of living cells are fed by the blood supply from underneath, whereas the upper dead cells only need water to ensure they're kept plump and smooth.
The epidermis is responsible for your coloring, as it holds the skin's pigment. It ranges in thickness from l/20-th of an inch on the palms and soles, to 1/200-th of an inch on the face.
The skin contains the following specialized organs:
Sebaceous glands are tiny organs which usually open into hair follicles on the surface of your skin. They produce an oily secretion, called sebum, which is your skin's natural lubricant.
The sebaceous glands are most concentrated on the scalp and face - particularly around the nose, cheeks, chin and forehead, which is why these are usually the most oily areas of your skin.
Sweat glands are all over your body. There are millions of them and their main function is to regulate your body temperature. When sweat evaporates on the skin's surface, the temperature of your skin drops.
Hairs grow from the hair follicles. They can help keep your body warm by trapping air underneath them. There are no hairs on the soles of your feet and palms of your hands.
are developed and maintained