BIOLOGIYA MORYA, 2016, Vol. 42, No. 3, pp. 215-223 |
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Morphofunctional characterization and ploidy levels of digestive gland cells in prosobranch gastropod molluscs (Prosobranchia: Gastropoda) Far Eastern Federal University, Vladivostok 690091 E-mail: The histological organization and ploidy levels of the digestive gland cells in 34 species of prosobranch gastropod molluscs belonging to the subclasses Patellogastropoda, Vetigastropoda, and Caenogastropoda of the orders Littorinimorpha and Neogastropoda were investigated with the use of histochemical methods and cytophotometry of nuclear DNA. Two general types of differentiated cells - digestive and basophilic - were determined in the epithelium of the digestive tubules. In Vetigastropoda and Neogastropoda species, all the cells are mostly diploid. In Patellogastropoda and Littorinimorpha, the digestive cells are diploid too, but basophilic cells reach polyploid levels of 4-8c in many species and even 4-8-16c in some species. Cases of somatic polyploidy in basophilic cells are considered as adaptive modifications of histogenesis associated with the peculiarities of the environment (intensified metabolism in osmotically tolerant Littorina and Lottia species), the duration of ontogenesis (a short life cycle in Lacunidae species) and specific food ration. Key words: Gastropoda, Prosobranchia, digestive gland, histology, physiology, somatic polyploidy, endopolyploidy. |
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