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  • Author: M. F. Kovtun x
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M. F. Kovtun

An unconventional approach to the study and analysis of ontogenesis, based on the duality of its nature is proposed: in the first case this is a phenomenon, in second case it is a process. As a phenomenon, ontogenesis covers all manifestations of living, providing the continuity of life on all the levels of its organization, ensures lifespan of a species, regardless of the individual‘s life, and thus the dynamic stability of the cycle of matter and energy flows, the evolution cycles, the biosphere and life in general. As a process it is the implementation of ontogenesis by the way of successive morphogeneses. There is a gap between these components of ontogenesis (the phenomenon and the process) that must be filled out. This is a complex task in the scope of the ontogenesis evolution problem (making the theory of ontogenesis).

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Ya. V. Stepanyuk and M. F. Kovtun

Abstract

The morphogenesis of the lake frog (Pelophylax ridibundus) vomeronasal organ was studied during different ontogenesis stages. The vomeronasal organ is laid after the formation of olfactory sacs, which are lined by olfactory epithelium, and after choan formation. Vomeronasal organ anlage takes place during G24 stage of larval development, which is the result of inflection and cell redistribution of olfactory epithelium rostroventral part. Formation of the vomeronasal organ finished at the beginning of metamorphosis. Apparently, vomeronasal organ appeared in aquatic Amphibia ancestors and after their transition from aquatic to terrestrial environment it developed new adaptive functions

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M. F. Kovtun and Ya. V. Stepanyuk

Abstract

The Development of Olfactory Organ of Lissotriton vulgaris (Amphibia, Caudata). Kovtun, M. F, Stepanyuk, Ya. V. - Using common histological methods, the morphogenesis of olfactory analyzer peripheral part of Lissotriton vulgaris (Amphibia, Caudata) was studied, during the developmental period starting with olfactory pit laying and finishing with definitive olfactory organ formation. Special attention is paid to vomeronasal organ and vomeronasal gland development. Reasoning from obtained data, we consider that vomeronasal organ emerged as the result of olfactory epithelium and nasal cavity differentiation.

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M. F. Kovtun and H. V. Sheverdyukova

Abstract

The theory of filembriogenesis is only an introduction to the problem’s development of ontogeny’ and phylogeny’ relation (hereinafter — «relation»). Discussions as to whether ontogeny creates phylogeny, or vice versa, are devoid of meaning. The opinion of O. Hertwig (Hertwig, 1906) that the ontogeny and phylogeny are two parallel and independent developmental processes is valid only in the first part; thesis about independence distorts the essence of «relation.» According to the authors, one of the essential characteristics of the «relation» is that ontogeny gives the material for phylogeny, and phylogeny renews ontogeny, leading away ontogeny from inbreeding; that ontogeny ensures the life continuity and phylogeny — its differentiation, that is, creates biodiversity; that ontogeny and phylogeny can exist and function only in conjunction or in parallel, changing places (in terms of priority) in the life evolution.

Open access

M. F. Kovtun, I. O. Lykova and L. P. Kharchenko

Abstract

The results of the macro-micromorphological structure of the digestive system of the waders and comparative analysis with the migrants of the Aves are presented. It was revealed that the digestive system of waders at the anatomical level has a universal structure typical for representatives of class Aves. As a result of histological studies of the structure of the digestive tract, it was found that the feature of the wall of the waders small intestine is the dense location of the crypt in its own plate of the mucous membrane throughout its length. High proliferative capacity of cambial crypt cells and their multilayered location provide high secretory and regenerative activity of enterocytes, which helps to restore the mucous membrane and intensify the digestive processes, especially during the active feeding of the waders at the migration stopover points. At this time, the length and mass of the intestine, the mass of the stomach and the liver increase, what is considered as a reaction to a large number of feeds in the intensive feeding of birds and indicates the plasticity of their digestive system. It is shown that the change in the morphometric parameters of the waders digestive system organs depending on the migration situation is an integral part of the adaptive mechanism of the migratory birds, which provides the basic need of the organism - fat accumulation. Th e content of general liver lipids, abdominal fat and thoracic muscles in 6 species of tundra warblers with varying degrees of fat accumulation at the migration stopover points in the Azov-Black Sea region was studied.