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| SKIN ANATOMY |
The skin is an organ of wrapping the entire outside surface of the body, is the heaviest and largest organ of the body. The entire skin weighs about 16% of body weight, in adults of about 2.7 to 3.6 kg and the extent of about 1.5 to 1.9 square meters. Skin thickness varied from 0.5 mm to 6 mm depending on the location, age and gender. Pellicle is located on the eyelids, penis, labium minus and the medial upper arm skin. While there is a thick skin on the palms, soles of the feet, back, shoulder and buttocks.
In embryological skin from two different layers, the outer layer is the epidermis, which is derived from the epithelial layer while the inner lining Ectoderm derived from the mesoderm is the dermis or korium which is a layer of connective tissue.
Epidermis
Epidermis is the thin outer layer of skin and avaskuler. Layered epithelium consisting of flattened horns, cells contain melanocytes, Langerhans and Merkel. Epidermal thickness varies at different places in the body, thickest on the palms of the hands and feet. The thickness of the epidermis is only about 5% of the total thickness of the skin. Regeneration occurs every 4-6 weeks. Epidermis consists of five layers (from the uppermost layer to the deepest):
1. Stratum corneum. Composed of keratinocytes cells that can peel and changed.
2. Stratum Lusidum Represent translucent lines, typically located on a thick leather soles and palms. There
In embryological skin from two different layers, the outer layer is the epidermis, which is derived from the epithelial layer while the inner lining Ectoderm derived from the mesoderm is the dermis or korium which is a layer of connective tissue.
Epidermis
Epidermis is the thin outer layer of skin and avaskuler. Layered epithelium consisting of flattened horns, cells contain melanocytes, Langerhans and Merkel. Epidermal thickness varies at different places in the body, thickest on the palms of the hands and feet. The thickness of the epidermis is only about 5% of the total thickness of the skin. Regeneration occurs every 4-6 weeks. Epidermis consists of five layers (from the uppermost layer to the deepest):
1. Stratum corneum. Composed of keratinocytes cells that can peel and changed.
2. Stratum Lusidum Represent translucent lines, typically located on a thick leather soles and palms. There
does not appear on the thin skin.
3. Stratum GranulosumDitandai by 3-5 layers of flattened polygonal cells are essentially in the middle and
3. Stratum GranulosumDitandai by 3-5 layers of flattened polygonal cells are essentially in the middle and
the cytoplasm is filled with coarse granules, called granule basofilik keratohialin containing histidine-rich
protein. There are Langerhans cells.
4. Stratum spinosum. There are files called tonofibril filament, filaments are considered to play an important
4. Stratum spinosum. There are files called tonofibril filament, filaments are considered to play an important
role to maintain the cohesion of cells and protects against abrasion effects. Epidermis at places continue
to have friction and pressure have a stratum spinosum with more tonofibril. Stratum basale and stratum
spinosum known as Malfigi layer. There are Langerhans cells.
5. Basale stratum (Stratum Germinativum). There is a great mitotic activity and is responsible for the
5. Basale stratum (Stratum Germinativum). There is a great mitotic activity and is responsible for the
constant renewal of epidermal cells. Epidermis is renewed every 28 days to migrate to the surface, this
depends on the location, age and other factors. Represents a single layer of cells that contain melanocytes.
Epidermis functions: barrier protection, the organization of cells, vitamin D and cytokine synthesis, cell division and mobilization, pigmentation (melanocytes) and the introduction of allergens (Langerhans cells).
Dermis
The most important part in the skin that is often considered as "True Skin". Consists of connective tissue that supports the epidermis and correlates with the subcutis tissue. Thickness varies, the thickest on the soles of about 3 mm.
Dermis consists of two layers:
* Papillary Layer; thin connective tissue containing sparse.
* Layer reticular; thick composed of dense connective tissue.
Thickening of collagen fibers and collagen synthesis decreases with increasing age. Elastin fibers is steadily increasing and thickening, human skin elastin content increased by approximately five times from fetuses to adults. Collagen in elderly intersect each other in large numbers and reduced elastin fibers causes the skin is lost kelemasannya and seemed to have many wrinkles. Dermis has many blood vessels network. Dermis also contains several epidermal derivatives of hair follicles, sebaceous glands and sweat glands. Skin quality depends much on whether a derivative of the epidermis in the dermis.
The function of the dermis: structural support, mechanical strength, the supply of nutrients, withstand shearing forces and the inflammatory response
Subcutis
Is the layer below the dermis or hypodermis consisting of layers of fat. This layer of connective tissue that connects there is a loose skin with underlying tissues. The number and size varies according to regions in the body and the circumstances of individual nutrients. Support the functioning of the blood supply to the dermis for regeneration.
Epidermis functions: barrier protection, the organization of cells, vitamin D and cytokine synthesis, cell division and mobilization, pigmentation (melanocytes) and the introduction of allergens (Langerhans cells).
Dermis
The most important part in the skin that is often considered as "True Skin". Consists of connective tissue that supports the epidermis and correlates with the subcutis tissue. Thickness varies, the thickest on the soles of about 3 mm.
Dermis consists of two layers:
* Papillary Layer; thin connective tissue containing sparse.
* Layer reticular; thick composed of dense connective tissue.
Thickening of collagen fibers and collagen synthesis decreases with increasing age. Elastin fibers is steadily increasing and thickening, human skin elastin content increased by approximately five times from fetuses to adults. Collagen in elderly intersect each other in large numbers and reduced elastin fibers causes the skin is lost kelemasannya and seemed to have many wrinkles. Dermis has many blood vessels network. Dermis also contains several epidermal derivatives of hair follicles, sebaceous glands and sweat glands. Skin quality depends much on whether a derivative of the epidermis in the dermis.
The function of the dermis: structural support, mechanical strength, the supply of nutrients, withstand shearing forces and the inflammatory response
Subcutis
Is the layer below the dermis or hypodermis consisting of layers of fat. This layer of connective tissue that connects there is a loose skin with underlying tissues. The number and size varies according to regions in the body and the circumstances of individual nutrients. Support the functioning of the blood supply to the dermis for regeneration.
Function subcutis / hypodermis: stick to the basic structure, thermal insulation, calorie reserves, control of body shape and mechanical shock absorber.
LEATHER vascularities
Arteries that nourish the skin form the plexus located between the papillary and reticular dermis layer and in addition the tissue between the dermis and subcutis. Small branch leaving this plexus memperdarahi dermis papilla, each papilla dermis had one artery and one branch ascending vein. In the epidermis there are no blood vessels but gets nutrients from the dermis through the epidermal membrane
SKIN PHYSIOLOGY
The skin is an organ that is essential for body functions such as enabling survival in various environmental conditions, as a barrier to infection, controlling body temperature (thermoregulation), sensation, eskresi and metabolism.
Protection function is to protect the skin from loss of fluid from the electrolyte, mechanical trauma, ultraviolet and as a barrier from invasion by pathogenic microorganisms. The sensation is one of the known functions of the skin in response to stimuli felt because of the many nerve endings as the region's lips, nipples and fingertips. Play a role in skin temperature regulation and fluid electrolyte balance. Thermoregulation is controlled by hipothalamus. Peripheral temperature undergo a process of balance through sweat, insessible loss from the skin, lungs and buccal mucosa. Skin temperature is controlled by the dilation of blood vessels or kontriksi skin. When the temperature increases occurred vasodilatation of blood vessels, then the body will reduce the temperature by removing heat from the skin by sending chemical signals that can increase blood flow in the skin. In the temperature decreases, the skin will vasoconstriction of blood vessels which then will retain heat.
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