Gametogenesis
Concept of gametogenesis, meiosis, spermatogenesis and oogenesis. Gametogenesis in mammals. Structure of the gametes. Sperm, egg and flagella structure. Sperm capacitation and egg cytoplasm. Egg maturation at the time of fertilization in various species.
Подобные документы
The study of variability of the morphology of pollen grains of the genus Pinus. Differences in the total amount of abnormal pollen under the influence of pests and pathogens of different nature. The possibility of diagnosing of biotic influence on plants.
статья, добавлен 04.12.2023The distribution of the water caltrop Trapa natans L. in Ukraine. This relict species had strongly declined in the early 1979s, but has now recovered and even excessively spread in the upper reaches of the Kaniv and Kyiv reservoirs on the Dnipro River.
статья, добавлен 11.07.2023Information about the xerophytic type of vegetation of the Daridag area is presented. Areas at an altitude of 1200-1600 m above sea level are characterized by plant species with mountain xerophytic vegetation. Mountain xerophytic flora is not homogeneous.
статья, добавлен 10.10.2024Feed plants are dynamically utilized by humans. This leads to a decreasing supply of feed plants. For this purpose, we studied the rare species of feed plants in the vegetation of Gunnut-Kapychik physiographic area where we conducted our research.
статья, добавлен 10.10.2024The development of diagnostic females Mordellid Beetles of the genus Stenalia Mulsant with the new species-specific trait outer morphology - female pygidium. General characteristics of the range of data beetles - in Central and Eastern Palearctic.
статья, добавлен 15.04.2014Growing conditions for fodder legume Lucerne (Medicago L.). Comparison of salt stress indices of two species (Medicago sativa, Medicago falcata) and two grades at the germination and growth stages. Analysis of the sensitivity of alfalfa to soil salinity.
статья, добавлен 20.03.2022The study of perennial grasses and shrubs growing on the territory of Azerbaijan. Researchof representatives of the Asteraceae family, characteristic of main species. Systematic analysis of the genus Cirsium Mill. in the flora in regions of the country.
статья, добавлен 10.10.2024The nature of institutions is nothing but their coming into being (nascimento) at certain times and in certain guises. Whenever the time and guise are thus and so, such and not otherwise are the institutions that come into being — Vico, The New Science.
статья, добавлен 11.08.2013Study of self-pollination of two species of flora – Gladiolus imbricatus and Iris sibirica (Iridaceae). Pollination by autogenous pollen grains on the last day of flowering. Lack of a mechanism for autonomous pollen transfer within the merantium.
статья, добавлен 28.09.2023Unclear conditions for the formation of basidiomas as the reason for the small number of species of fungi that can be grown in industrial culture. Features of the initiation of the formation of basidiomas of medicinal macromycetes in a pure culture.
статья, добавлен 16.04.2020Study of the genus Campanula, widespread in the northern hemisphere and of importance for the flora of the Caucasus. Comparison of the history of the study of the genus, its geographical distribution, and taxa found in the flora of Karabakh and Zangezur.
статья, добавлен 04.09.2024Information about the brown long-eared bats in Luhansk region, to consider the prevalence, typical habitats and analyze morphometric peculiarities of the species. The presence of a stable local population of the brown long-eared bats in Luhansk region.
статья, добавлен 25.03.2016Evaluation and analysis of relative degree of drought resistance by water content of tissue. Assessment of relative drought resistance by water-holding capacity of leaves genus momordica (cucurbitaceae) introduced under the conditions of Belgorod region.
статья, добавлен 29.11.2016Study and analysis of antagonistic activity of facultative-anaerobic endosporeforming bacteria strains isolated from deep-water sediments. Study of the relationship between the species of the strain, the horizon of its origin and antagonistic activity.
статья, добавлен 20.08.2020Formation of the classical paradigm of natural science using the concepts of classical physics: matter, force, interaction, space, time. Factors of the formation of an extensive picture of the material world, the consequences and causes of the process.
статья, добавлен 02.03.2019Comparison of the physical development of children 7-8 years old over a 12-year period of time. Analysis of children with a normal physical development and with disharmony due to excessive body weight. The connection of this phenomenon with gender.
статья, добавлен 25.03.2018- 117. Анализ структурного разнообразия провируса BLV на основании температурных кривых Real Time SYBRgreen
Изучение структурного разнообразия провируса BLV на основании температурных кривых. По нуклеотидному составу, на основании температурных пиков, распределение выборки на группы, соответствующие международной классификации генотипов провируса BLV (I–VII).
статья, добавлен 25.03.2018 The basic metabolic processes, accompanying the neutralization of pollutants in the soil and water environment. Hydrolysis of starch, lactose, proteins and fats. Dividing a gelatin-containing agar plate into four section. Using an aseptic technique.
реферат, добавлен 16.07.2017Metchnikoff's life. A Biographical Note. Metchnikoff's Autobiographical Retrospection of His Phagocytosis Hypothesis. Harmony and Disharmony - Metchnikoff's Metaphysics. The Concept of the Embryonic Layers. Metchnikoff's Early Opinion of Recapitulation.
монография, добавлен 27.02.2017Приготування зразків деградованої дезоксирибонуклеїнової кислоти. Визначення точності та достовірності системи 7500 PCR Real Time/Quantifiler Human. Стабільність системи, вплив інгібіторів на реакцію полімеразної ланцюгової реакції у реальному часі.
статья, добавлен 24.08.2018The essence of the concept of the energy mechanism of the functioning of the human body at the micro-and macro-level of energy - mass compaction. Automating the diagnosis and treatment of diseases through the control signals of quantum computers.
статья, добавлен 19.02.2021Remarkable passages in the Foundations of arithmetic. Frege on extensions of concepts, from 1884 to 1903. Conceptual uncertainty and frege's rationalism. Contextual definition, concept and object of ontological options, incomplete understanding.
научная работа, добавлен 09.09.2012Relevance of the innovation and investment activities of the state in the segment of the food supply as the possibility of preserving the biological life of the Ukrainian nation. Innovative-investment concept of conservation of vital national resources.
статья, добавлен 14.05.2018- 124. Molecular and elemental composition of humic acidsisolated from selected soils of the Russian Arctic
Methods for assessing the degree of stabilization of polar soil organic matter. Analysis of the molecular and elemental composition of humic acids isolated from individual soils of the Russian Arctic. The essence of the concept of "aliphatic fragments".
статья, добавлен 05.10.2020