Dermis
The distribution of the bloodvessels in the skin of the sole of the foot. (Corium - TA alternate term for dermis - is labeled at upper right.)
A diagrammatic sectional view of the skin (magnified). (Dermis labeled at center right.)
Gray's	subject #234 1065
MeSH	Dermis
Dorlands/Elsevier	d_11/12289496

The dermis is a layer of skin beneath the epidermis that consists of connective tissue and cushions the body from stress and strain. The dermis is tightly connected to the epidermis by a basement membrane. It also harbors many nerve endings that provide the sense of touch and heat. It contains the hair follicles, sweat glands, sebaceous glands, apocrine glands and blood vessels. The blood vessels in the dermis provide nourishment and waste removal to its own cells as well as the Stratum basale of the epidermis. Image File history File links Gray942. ... Image File history File links Gray940. ... Medical Subject Headings (MeSH) is a huge controlled vocabulary (or metadata system) for the purpose of indexing journal articles and books in the life sciences. ... Elseviers logo. ... In zootomy and dermatology, skin is the largest organ of the integumentary system made up of multiple layers of epithelial tissues that guard underlying muscles and organs. ... It has been suggested that this article or section be merged with skin. ... Connective tissue is one of the four types of tissue in traditional classifications (the others being epithelial, muscle, and nervous tissue. ... ... A hair follicle is part of the skin that grows hair by packing old cells together. ... Sweating (also called perspiration or sometimes transpiration) is the loss of a watery fluid, consisting mainly of sodium chloride and urea in solution, that is secreted by the sweat glands in the skin of mammals. ... Schematic view of a hair follicle with sebaceous gland. ... A diagrammatic sectional view of the skin (magnified). ... f you all The blood vessels are part of the circulatory system and function to transport blood throughout the body. ...

Structure

The dermis is structurally divided into two areas: a superficial area adjacent to the epidermis, called the papillary region, and a deep thicker area known as the reticular region.

Papillary region

The papillary region is composed of loose areolar connective tissue. It is named for its fingerlike projections called papillae, that extend toward the epidermis. The papillae provide the dermis with a "bumpy" surface that interdigitates with the epidermis, strengthening the connection between the two layers of skin. Gel-like matrix with all three fiber types Areoloar tissue is the most common connnective tissue type and can be found in the skin as well as in places that connect epithelium to other tissues. ...

In the palms, fingers, soles, and toes, the influence of the papillae projecting into the epidermis forms contours in the skin's surface. These are called friction ridges, because they help the hand or foot to grasp by increasing friction. Friction ridges occur in patterns (see fingerprint) that are genetically determined and are therefore unique to the individual, making it possible to use fingerprints or footprints as a means of identification. Friction is the force that opposes the relative motion or tendency toward such motion of two surfaces in contact. ... The tip of a finger showing the friction ridge structure. ...

Reticular region

The reticular region lies deep in the papillary region and is usually much thicker. It is composed of dense irregular connective tissue, and receives its name from the dense concentration of collagenous, elastic, and reticular fibers that weave throughout it. These protein fibers give the dermis its properties of strength, extensibility, and elasticity. Tropocollagen triple helix. ... Elastic fibers (or yellow fibers) are bundles of proteins (elastin) found in connective tissue and produced by fibroblasts and smooth muscle cells in arteries. ... Reticular fibers are the structural fiber in some connective tissues. ... A representation of the 3D structure of myoglobin, showing coloured alpha helices. ...

Located within the reticular region are also the hair roots, sebaceous glands, sweat glands, receptors, nails, and blood vessels. The root of the hair ends in an enlargement, the hair bulb, which is whiter in color and softer in texture than the shaft, and is lodged in a follicular involution of the epidermis called the hair follicle. ... Schematic view of a hair follicle with sebaceous gland. ... Sweating (also called perspiration or sometimes transpiration) is the loss of a watery fluid, consisting mainly of sodium chloride and urea in solution, that is secreted by the sweat glands in the skin of mammals. ... Anatomy In anatomy, a nail is a horn-like piece at the end of a humans or an animals finger or toe. ... f you all The blood vessels are part of the circulatory system and function to transport blood throughout the body. ...

Tattoo ink is injected into the dermis. Stretch marks from pregnancy are also located in the dermis. This article or section does not cite any references or sources. ... Look up stria in Wiktionary, the free dictionary. ... A pregnant woman near the end of her term Pregnancy is the carrying of one or more embryos or fetuses by female mammals, including humans, inside their bodies. ...

Additional images

Cross-section of all skin layers. Image File history File linksMetadata Skin. ...

External links

• Diagrams at cdc.gov
• Diagram at cdc.gov
• Histology at BU 08201oba - "Integument: three layers, reticular dermis, papillary dermis "