1-2-6.Cross section of skin：Dermis
	●It is composed between the collagen fiber, the elastoma, and that of the substrate the filling dermis that supports epidermis from the under. Dermis is distinguished by three (mamillary body, the lower layer of mamillary, and zona reticularis). The collagen fiber is a string with white protein of collagen. It is Erastin of the elastoma for this to fill with the corium layer like the reticulation, and to exist at the intersection of the string. Erastin is made of the protein, too. Substrate ●The substrate is a gel material that contains enough moisture such as the proteins such as collagen besides Muco polysaccharides such as the hyaluronic acid and the chondroitin sulfate, albumins, and globulins and minerals of the inorganic salt. The moisture between each fiber and the cell is maintained. ●Collagen fiber, elastic fiber, and the substrate that composes dermis are made from fibroblast cell. This cell is reborn from five in six years. There are a sweat gland, a glandulae sebaceae, a hair, and a lot of blood vessels, lymph ducts, and nerves in dermis, and the nourishment to the skin, metabolizing, and the skin function of sense are borne. Mamillary body ●Mamillary body that projects to the dermis side where it touched stratum basale and the stratum mamillary that is below soon can do with a detailed uniting fiber and the capillary, and contain enough moisture. Reticular layer ●Because collagen fiber and erastic fiber queue up closely in the reticulation, it is said reticular layer. It is the thickest layer in stratum dermis. The elasticity of the skin of which the role strength and is the movement of the skin is borne. The quality of the fiber changes, is cut, and it causes wrinkle by decreasing by aging.