MEDICAL BIOLOGY, ANATOMY, HUMAN PHYSIOLOGY AND PATHOLOGY - Y.I. Fedoniuk 2010

BIOLOGY

CHAPTER 1. BIOLOGICAL FOUNDATIONS OF HUMAN VITAL ACTIVITY

1.3. MOLECULAR-GENETIC AND CELLULAR LEVELS OF LIFE ORGANIZATION

1.3.4. Organization of Cells in Time

One of the fundamental tenets of Cell Theory is that Cells do not arise de novo, but rather form through the reproduction of pre-existing cells. This principle was formulated by the German pathologist R. Virchow in 1858: "omnis cellula e cellula" ("every cell stems from another cell"). Cell reproduction (proliferation) occurs via division. Cell Division takes place in two stages: first, The Nucleus divides (karyokinesis), followed by the Cytoplasm (cytokinesis). The primary types of Introduction/5.html">Eukaryotic Cell division are Mitosis and Meiosis. Mitosis occurs in all somatic cells, whereas meiosis takes place during The formation of Germ Cells. In addition to mitosis and meiosis, amitosis is distinguished as a direct division of somatic cells in which the nucleus divides by constriction without forming a mitotic apparatus. This type of division is believed to occur in malignant tumor cells.



Last update: 08/08/2026

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