Saturday, November 22, 2008
Saturday, November 8, 2008
Vehicle Cleaning Supplies
Apparato Tegumentario
L'apparato tegumentario è un insieme di organi e di strutture : la cute e la tela sottocutanea . La cute riveste il corpo esternamente; ad essa sono annesse le cosiddette "produzioni cutanee",che sono: i peli, le unghie, le ghiandole sebacee , ghiandole sudoripare e le mammelle. La tela sottocutanea/derma, si estende al di sotto della cute. La cute/pelle è una membrana continua, elastica e distensibile; essa svolge funzioni importanti: di protezione,secrezione ed escrezione e inoltre di termoregolazione , attraverso la presenza di ghiandole sudoripare, grazie alle quali la temperatura corporea riesce a mantenersi costante. La cute presenta colorito diverso in base alle razze, ma in realtà ciò è dovuto a diversi fattori, ossia: la melanina , che determina il colore nero; il sangue , che dona la tonalità rossa, il carotene , che dà la sfumatura giallastra. La superficie esterna della cute, presenta piccoli ma innumerevoli solchi,che sono le fossete hair and outlet openings of the sweat glands. Microscopically distinguish three different layers: the more superficial epidermis, the stratum most abundant "the dermis and the innermost layer" the hypodermis. The skin epithelium is a compound coating, in which the depth to the surface can be distinguished: the germinal layer, the stratum granulosum, the stratum corneum layer and polished. Of these layers, only the first and last points are thick, while the intermediates are very thin. The germinal layer is composed of many cellular plans, the deep layer consists of prismatic cells that make up the basal layer of the germ, while the overlying strata consist polyhedral cells that form the spinous layer of the germ. The germ cells, contain within their cytoplasm the tonofibrille, each of which is formed by a bunch of tonofilamenti. The granular layer is composed of granules of keratin, a phospholipid material, which passes in the intercellular spaces, giving permeability. In the glossy layer, so called because of its bright appearance, the cytoplasm consists of dense filaments and drops eleidina , and sulfur-rich fluids that would have the task of impeding the evaporation process in the epidermis. the stratum corneum, is composed of cells corneificate then formed by keratin. These cells are flattened considerably, they are detached to the surface forming layer separated, then crumble and fall. The dermis layer of connective tissue is a robust, durable and compact. Its outer surface is irregular due to the presence of minute measurements: the dermal papillae, and longitudinal surveys: the dermal ridges. The dermis is also composed of dense connective tissue, composed of a large amount of collagen fibers and elastic fibers.
Thursday, November 6, 2008
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