NationMaster - Encyclopedia: Sebaceous gland

The sebaceous glands are glands found in the skin of mammals. They secrete an oily substance called sebum (Latin, meaning fat or tallow) that is made of fat (lipids) and the debris of dead fat-producing cells. These glands exist in humans throughout the skin except in the palms of the hands and soles of the feet. Sebum acts to protect and waterproof hair and skin, and keep them from becoming dry, brittle, and cracked. It can also inhibit the growth of microorganisms on skin. Image File history File links Source: http://www. ... Image File history File links Source: http://www. ... A gland is an organ in an animals body that synthesizes a substance for release such as hormones, often into the bloodstream (endocrine gland) or into cavities inside the body or its outer surface (exocrine gland). ... In zootomy and dermatology, skin is an organ of the integumentary system made up of multiple layers of epithelial tissues that guard underlying muscles and organs. ... Orders Multituberculata (extinct) Palaeoryctoides (extinct) Triconodonta (extinct) Subclass Australosphenida Ausktribosphenida Monotremata Subclass Eutheria (excludes extinct ancestors) Afrosoricida Anagaloidea (extinct) Arctostylopida (extinct) Artiodactyla Carnivora Cetacea Chiroptera Cimolesta (extinct) Cingulata Creodonta (extinct) Condylarthra (extinct) Dermoptera Desmostylia (extinct) Dinocerata (extinct) Embrithopoda (extinct) Hyracoidea Insectivora Lagomorpha Leptictida (extinct) Litopterna (extinct) Macroscelidea Mesonychia (extinct) Notoungulata... Latin is an ancient Indo-European language originally spoken in Latium, the region immediately surrounding Rome. ... For other uses, see Fat (disambiguation). ... Tallow is rendered beef or mutton fat, which was originally suet. ... Lipids are a class of hydrocarbon-containing organic compounds essential in providing stored energy and organ protection within a living organism. ... Young Girl Fixing her Hair, by Sophie Gengembre Anderson Hair is a filamentous outgrowth of dead cells from the skin, found mainly in mammals. ...

Sebaceous glands can usually be found in hair-covered areas where they are connected to hair follicles to deposit sebum on the hairs, and bring it to the skin surface along the hair shaft. The structure consisting of hair, hair follicle and sebaceous gland is known as pilosebaceous unit. Sebaceous glands are also found in non haired areas of lips, eyelids, penis, labia minora and nipples; here the sebum reaches the surface through ducts. In the glands, sebum is produced within specialized cells and is released as these cells burst; sebaceous glands are thus classified as holocrine glands. A hair follicle is part of the skin that grows hair by packing old cells together. ... A hair follicle is part of the skin that grows hair by packing old cells together. ... The lips of a female Lips are a visible organ at the mouth of humans and many animals. ... An eyelid is a thin fold of skin and muscle that covers and protects an eye. ... The penis (plural penises, penes) is an external male sexual organ. ... Parts of a vulva The external genital organs of the female are collectively known as the vulva (also sometimes called the pudenda). ... The udder of a cow with nipples showing In its most general form, a nipple is an appurtenance from which a fluid emanates, in this instance breast milk, to nurture a mothers young. ... Cells in culture, stained for keratin (red) and DNA (green). ... Exocrine gland refers to glands that secrete their products and temporarily store their secretions in a duct. ...

Sebum is odorless, but its bacterial breakdown can produce odors. Sebum is the cause of some people experiencing "oily" hair if it is not washed for several days. Earwax is partly sebum. On the eyelids, Meibomian glands are a specialized form of sebaceous gland that secrete sebum into the tears coating the eye to prevent evaporation. Subgroups Actinobacteria Aquificae Bacteroidetes/Chlorobi Chlamydiae/Verrucomicrobia Chloroflexi Chrysiogenetes Cyanobacteria Deferribacteres Deinococcus-Thermus Dictyoglomi Fibrobacteres/Acidobacteria Firmicutes Fusobacteria Gemmatimonadetes Nitrospirae Planctomycetes Proteobacteria Spirochaetes Thermodesulfobacteria Thermomicrobia Thermotogae Bacteria (singular: bacterium) are microscopic, unicellular organisms. ... Wet-type human earwax on a cotton swab. ... The Meibomian glands (Glandulae tarsales) are a special kind of sebaceous glands at the rim of the eyelids, where they are responsible for to supply sebum, an oily substance that prevents evaporation of the eyes tear film. ... Tears are commonly associated with crying Tears are a liquid produced by the bodys process of lacrimation to clean and lubricate the eyes. ... Closeup of a blue-green human eye. ...

The composition of sebum varies from species to species; in humans, the lipid content consists of about 25% wax monoesters, 41% triglycerides, 16% free fatty acids, and 12% squalene. ^[1] Image File history File links Gray944. ... Image File history File links Gray944. ... It has been suggested that Medium Chain Triglycerides be merged into this article or section. ... In chemistry, especially biochemistry, a fatty acid is a carboxylic acid often with a long unbranched aliphatic tail (chain), which either saturated or unsaturated. ... Squalene is a natural organic compound originally obtained for commercial purposes primarily from shark liver oil, though there are botanical sources as well, including rice bran, wheat germ, and olives. ...

Certain species of Demodex mites feed on sebum and are commonly found in the sebaceous glands of mammals, including those of humans. Species Demodex folliculorum Demodex brevis Demodex canis The demodex mite is a tiny parasitic mite which lives around human hair follicles, particularly those of the eyelashes and eyebrows (Demodex folliculorum hominis) or in sebaceous glands connected to hair follicles (Demodex brevis). ...

The activity of the sebaceous glands increases during puberty because of heightened levels of androgens. Puberty refers to the process of physical changes by which a childs body becomes an adult body capable of reproduction. ... Androgen is the generic term for any natural or synthetic compound, usually a steroid hormone, that stimulates or controls the development and maintenance of masculine characteristics in vertebrates by binding to androgen receptors. ...

Sebaceous glands are involved in skin problems such as acne and keratosis pilaris. A blocked sebaceous gland can result in a sebaceous cyst. A condition involving enlarged sebaceous glands is known as sebaceous hyperplasia. The prescription drug isotretinoin significantly reduces the amount of sebum produced by the sebaceous glands, and is used to treat acne. The extreme use (up to 10 times doctor prescribed amounts) of anabolic steroids by bodybuilders for muscle gain and repartitioning effects tend to stimulate the sebaceous glands which can cause acne.^[2] Sebaceous gland carcinoma is a rare and aggressive form of cancer involving the sebaceous glands; sebaceous adenoma is a more benign neoplasm of the sebaceous glands. Keratosis pilaris (KP) is a very common genetic follicular condition that is manifested by the appearance of rough bumps on the skin and hence colloqually referred to as chicken skin. Primarily, it appears on the back and outer sides of the upper arms, but can also occur on thighs and... A sebaceous cyst (a form of trichilemmal cyst; also called: keratin cyst; sometimes wrongly called: epidermal cyst or epidermoid cyst (see ICD-10 L72. ... Sebaceous hyperplasia is a disorder of the sebaceous glands in which they become enlarged. ... Isotretinoin (INN) (IPA: ) is a medication used for the treatment of severe acne. ... Chemical structure of the natural anabolic hormone testosterone, 17b-hydroxy-4-androsten-3-one. ... Bodybuilder Anders Graneheim (Sweden) Bodybuilding is the sport of developing muscle fibers through the combination of weight training, increased caloric intake, and rest. ... Cancer is a class of diseases or disorders characterized by uncontrolled division of cells and the ability of these cells to invade other tissues, either by direct growth into adjacent tissue through invasion or by implantation into distant sites by metastasis. ... Neoplasia (literally: new growth) is sudden and abnormal growth in a tissue or organ. ...

The sebaceous glands of a human fetus in utero secrete a substance called Vernix caseosa, a "waxy" or "cheesy" white substance coating the skin of newborns. Fetus at eight weeks For other uses, see Fetus (disambiguation). ... In Utero is the third and final studio album from the American grunge band, Nirvana. ... Vernix, also known as Vernix caseosa, is the waxy or cheesy white substance found coating the skin of newborn humans. ...

The preputial glands of mice and rats are large modified sebaceous glands that produce pheromones. Preputial glands are exocrine glands that are located in front of the genitals of some mammals and produce pheromones. ... Feral mouse A mouse (Plural mice) is a mammal that belongs to one of numerous species of small rodents. ... Species 50 species; see text *Several subfamilies of Muroids include animals called rats. ... Fanning honeybee exposes Nasonov gland (white-at tip of abdomen) releasing pheromone to entice swarm into an empty hive A pheromone is any chemical or set of chemicals produced by a living organism that transmits a message to other members of the same species. ...

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Categories: Integumentary system | Glands | Exocrine system For the unrelated Jesuit university in Chestnut Hill, see Boston College. ... In zootomy, the integumentary system is often the largest organ system of an animal, comprising skin, hair, feathers, scales, nails, skin glands and their products (sweat, slime). ... In zootomy and dermatology, skin is an organ of the integumentary system made up of multiple layers of epithelial tissues that guard underlying muscles and organs. ... Sweating (also called perspiration or sometimes transpiration) is the loss of a watery fluid, consisting mainly of sodium chloride (commonly known as salt) and urea in solution, that is secreted by the sweat glands in the skin of mammals. ... Young Girl Fixing her Hair, by Sophie Gengembre Anderson Hair is a filamentous outgrowth of dead cells from the skin, found mainly in mammals. ... Nails: left hand, adult human male Anatomy In anatomy, a nail is a horn-like piece at the end of an animal finger or toe. ... In zootomy and dermatology, skin is an organ of the integumentary system made up of multiple layers of epithelial tissues that guard underlying muscles and organs. ... Epidermis is the outermost layer of the skin. ... The stratum corneum (the horny layer) is the outermost layer of the epidermis, and comprises the surface of the skin. ... The Stratum Lucidum is one of the layers of the Epidermis. ... Stratum granulosum contains 3 to 5 rows of flattened cells whose cytoplasm contains small granules. ... It is a multiple-layered arrangement of cuboidal cells containing molecular bridges that conect them to adjacent cells. ... Stratum germinativum or stratum basale is the layer of keratinocytes that lies at the base of the epidermis immediately above the dermis. ... The dermis is the layer of skin beneath the epidermis, that consists of connective tissue and cushions the body from stress and strain. ... The distribution of the bloodvessels in the skin of the sole of the foot. ...