Skin is the soft outer tissue covering of vertebrates with three main functions: protection and sensation. Other animal coverings, such as the arthropod exoskeleton, have different developmental origin and chemical composition; the adjective cutaneous means "of the skin". In mammals, the skin is an organ of the integumentary system made up of multiple layers of ectodermal tissue, guards the underlying muscles, bones and internal organs. Skin of a different nature exists in amphibians and birds. All mammals have some hair on their skin marine mammals like whales and porpoises which appear to be hairless; the skin is the first line of defense from external factors. For example, the skin plays a key role in protecting the body against pathogens and excessive water loss, its other functions are insulation, temperature regulation and the production of vitamin D folates. Damaged skin may heal by forming scar tissue; this is sometimes depigmented. The thickness of skin varies from location to location on an organism.
In humans for example, the skin located under the eyes and around the eyelids is the thinnest skin in the body at 0.5 mm thick, is one of the first areas to show signs of aging such as "crows feet" and wrinkles. The skin on the palms and the soles of the feet is the thickest skin on the body; the speed and quality of wound healing in skin is promoted by the reception of estrogen. Fur is dense hair. Fur augments the insulation the skin provides but can serve as a secondary sexual characteristic or as camouflage. On some animals, the skin is hard and thick, can be processed to create leather. Reptiles and fish have hard protective scales on their skin for protection, birds have hard feathers, all made of tough β-keratins. Amphibian skin is not a strong barrier regarding the passage of chemicals via skin and is subject to osmosis and diffusive forces. For example, a frog sitting in an anesthetic solution would be sedated as the chemical diffuses through its skin. Amphibian skin plays key roles in everyday survival and their ability to exploit a wide range of habitats and ecological conditions.
Mammalian skin is composed of two primary layers: the epidermis, which provides waterproofing and serves as a barrier to infection. It forms a protective barrier over the body's surface, responsible for keeping water in the body and preventing pathogens from entering, is a stratified squamous epithelium, composed of proliferating basal and differentiated suprabasal keratinocytes. Keratinocytes are the major cells, constituting 95% of the epidermis, while Merkel cells and Langerhans cells are present; the epidermis can be further subdivided into the following strata or layers: Stratum corneum Stratum lucidum Stratum granulosum Stratum spinosum Stratum basale Keratinocytes in the stratum basale proliferate through mitosis and the daughter cells move up the strata changing shape and composition as they undergo multiple stages of cell differentiation to become anucleated. During that process, keratinocytes will become organized, forming cellular junctions between each other and secreting keratin proteins and lipids which contribute to the formation of an extracellular matrix and provide mechanical strength to the skin.
Keratinocytes from the stratum corneum are shed from the surface. The epidermis contains no blood vessels, cells in the deepest layers are nourished by diffusion from blood capillaries extending to the upper layers of the dermis; the epidermis and dermis are separated by a thin sheet of fibers called the basement membrane, made through the action of both tissues. The basement membrane controls the traffic of the cells and molecules between the dermis and epidermis but serves, through the binding of a variety of cytokines and growth factors, as a reservoir for their controlled release during physiological remodeling or repair processes; the dermis is the layer of skin beneath the epidermis that consists of connective tissue and cushions the body from stress and strain. The dermis provides tensile strength and elasticity to the skin through an extracellular matrix composed of collagen fibrils and elastic fibers, embedded in hyaluronan and proteoglycans. Skin proteoglycans are varied and have specific locations.
For example, hyaluronan and decorin are present throughout the dermis and epidermis extracellular matrix, whereas biglycan and perlecan are only found in the epidermis. It harbors many mechanoreceptors that provide the sense of touch and heat through nociceptors and thermoreceptors, it contains the hair follicles, sweat glands, sebaceous glands, apocrine glands, lymphatic vessels and blood vessels. The blood vessels in the dermis provide nourishment and waste removal from its own cells as well as for the epidermis; the dermis is connected to the epidermis through a basement membrane and is structurally divided into two areas: a superficial area adjacent to the epidermis, called the papillary region, a deep thicker area known as the reticular region. The papillary region is composed of loose areolar connective tissue; this is named for its fingerlike projections called papillae. The papillae provide the dermis with a "bumpy" surface that interdigitates with the epidermis, strengthening the connection between the t
Tippi Benjamine Okanti Degré is a French woman best known for spending her youth in Namibia among wild animals and tribes people. In 2002–03, she was the presenter of Around the World with Tippi, six wildlife and environmental TV documentaries. Tippie Degré was born in Windhoek, Namibia, on June 4, 1990 to wildlife photographer-filmmaker parents and was raised in the bush for the first ten years of her life in Southern Africa, she was named after the American actress Tippi Hedren. During her childhood in Namibia, Degré befriended animals she lived among including a 28-year old elephant Abu, a leopard nicknamed J&B, giraffes, a banded mongoose, an ostrich, meerkats, a cheetah, a caracal, snakes, a giant bullfrog and chameleons. In 2000, Degré wrote the novel Tippi - My Book of Africa, based on her life in Namibia, South Africa and Madagascar where she lived among wild animals and with tribes people, the San Bushmen and the Himbas. In 2001, she was the Godmother of the World Wide Fund for Nature with the famous French actor and director Jacques Perrin, in France.
In 2002–03, Tippi presented six wildlife and environmental TV documentaries for the Discovery Channel. A documentary film on her experiences, Le Monde Selon Tippi was released in 1997. Around the World with Tippi was released in 2004, directed by Jeanne Mascolo de Filippis. Degré studied cinema and audiovisuals in France. Active in conservation and in the documentary film industry, she is a speaker and is the director of "El Petit FICMA," the children's section of the FICMA International Environmental Film Festival. Notes Further reading Ody, Joelle. Tippi of Africa. New Holland Publishers. ISBN 978-1-86872-083-5. Degré, Tippi. My Book of Africa. Struik. ISBN 978-1-77007-029-5. Official website Tippi Degré on IMDb Le Monde Selon Tippi at the Internet Movie Database
Michele Camporese is an Italian footballer who plays as a defender for Pordenone. Born in Pisa, Camporese is a product of Fiorentina's youth system, he made his debut for the Viola in the Coppa Italia tie against Empoli on 26 October 2010, replacing Alessandro Gamberini in the 66th minute and played the whole extra time. Fiorentina won the match 1–0 assuring qualification to the successive round. On 20 November 2010, he made his Serie A debut, replacing the injured Cesare Natali at half time in the match against Milan in San Siro. In the next match he replaced suspended Per Krøldrup as starting centre back, partnered with Alessandro Gamberini against Juventus. On 13 February 2011 he scored. In November 2011 he signed a new 5-year contract with La Viola. On 13 July 2013, Fiorentina confirmed on their website that Michele Camporese had joined Cesena on a season-long loan. On 25 July 2015, Camporese departed Fiorentina for Empoli after spending five seasons in Florence, it was confirmed by Empoli that he had agreed a contract until 30 June 2018.
On 18 July 2019, he signed a 2-year contract with Pordenone. Camporese has played for every Italy's youth team level, except for the U-20. With the Italy U-17 team he capped twice at the 2009 UEFA European Under-17 Football Championship qualifying round and another two times in the elite round. In the final tournament, his only appearance arrived as a second half cameo in the semi-final defeat against Germany U-17, he started all four matches in 2009 FIFA U-17 World Cup, in which the Azzurrini bowed out from the competition after defeat against Switzerland in the quarter finals. With Italy U-19 he played. Under the new regime of Ciro Ferrara, he received his first call-up for Italy U-21 in November 2010, he made his debut on 17 November 2010, replacing Riccardo Brosco in the first half of the friendly match, winning Turkey 2–1. FIGC National Teams Archive Michele Camporese – FIFA competition record