. Practical anatomy of the rabbit : an elementary laboratory textbook in mammalian anatomy . Rabbits; Anatomy, Comparative. Epithelial Tissues. 21 Epithelial Tissues. Epithelial tissues are distinguished chiefly as surface invest- ments, such as those of the exterior of the body, the interior of the alimentary canal, the lungs, the respiratory and accessory respira- tory tracts, and the ducts of the urinogenital organs. In all epithelia the cellular feature is a prominent one, and it is largely for this reason that as lining membranes they are not conspicuous in gross structure. They are notew
. Practical anatomy of the rabbit : an elementary laboratory textbook in mammalian anatomy . Rabbits; Anatomy, Comparative. Epithelial Tissues. 21 Epithelial Tissues. Epithelial tissues are distinguished chiefly as surface invest- ments, such as those of the exterior of the body, the interior of the alimentary canal, the lungs, the respiratory and accessory respira- tory tracts, and the ducts of the urinogenital organs. In all epithelia the cellular feature is a prominent one, and it is largely for this reason that as lining membranes they are not conspicuous in gross structure. They are noteworthy, however, for their products, the hairs and the various kinds of secreting organs or glands. The epithelium of the skin (Fig. 2) is known as the epidermis or scarf-skin. It is stratified, , composed of several layers deep of cells, of which the deeper are formative, growing cells, while those at the surface are flattened squamous cells, and are successively discarded. The several layers combined produce but a thin membrane. It extends over the entire surface of the body and connects at certain points with the epithelia of the internal sur- faces. It is supported by a thick resistant layer of connective tissue which forms the true skin or corium. The epithelium of the internal sur- faces forms the chief portion of the mucous membranes. In the greater portion of the alimentary tract the epithelial layer is simple or one layered and is associated with a thin layer of smooth muscle to form a mucous tunic (Fig. 16, ). The coating of hairs on the surface of the body, the presence of which is a notable mammalian feature, is a protective invest- ment arising from the epidermis. A hair is produced by the modification of the central portion of an ingrowth of the epidermis, termed the hair follicle (Fig. 2, f). The latter contains at its base a small elevation of the underlying vascular connective tissue, the hair papilla, through which the structure is nourished. On. Fig.
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Keywords: ., bookcentury1900, bookdecade1920, booksubjectanatomy, bookyear1921
