Histochemical characterization and functional significance of the epidermal gland cells in some invertebrates in phylogenetic aspect
Stoliarova, M.V.; Val'kovich, É I.
Morfologiia 137(5): 77-85
2010
ISSN/ISBN: 1026-3543 PMID: 21500440 Document Number: 644800
This paper reviews the basic results of findings on the structure and function of the epidermal gland cells in some invertebrates of different levels of organization. These data are compared with the results on the higher animals. Histochemical affinities of the epidermal gland cells in different animals are considered. The presence of the universal (ancient) cell types also found in mammals and in human is suggested. Marine invertebrate groups considered in this paper are characterized by a presence of a simple ciliated surface epithelium which fulfills different functions: locomotor, secretory, receptor, barrier, protective and absorption. In the process of phylogenesis, the epidermis of chordates underwent structural changes and intensification of protective function took place with the appearance of new protective mechanisms. The conclusion is done that the evolutionary development of surface epithelium is determined by its adaptation to environmental conditions and by the level of general organization; it followed the direction of intensification of protective function with the help of different mechanisms - mucus production, increase of cell layers number, intensive formation of cytoplasmic filaments, appearance of special protective structures in the form of cuticle or corneous layer.