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  • Cell - Mitosis, Cytokinesis, Prokaryotes | Britannica
    Cell - Mitosis, Cytokinesis, Prokaryotes: In unicellular organisms, cell division is the means of reproduction; in multicellular organisms, it is the means of tissue growth and maintenance Survival of the eukaryotes depends upon interactions between many cell types, and it is essential that a balanced distribution of types be maintained This is achieved by the highly regulated process of
  • Sclerenchyma | Description, Types, Function | Britannica
    Sclerenchyma, in plants, support tissue composed of any of various kinds of hard woody cells Mature sclerenchyma cells are usually dead and have thick secondary cell walls They are commonly found as fibers or sclereids in nongrowing regions of plant bodies, such as in seed coats, bark, or vascular bundles
  • cell - Students | Britannica Kids | Homework Help
    The cell membrane is semipermeable—that is, some substances can pass through it but others cannot This characteristic enables the cell to admit or block substances from the surrounding fluid and to excrete waste products into its environment The cell membrane is composed of two thin layers of phospholipid molecules studded with large proteins
  • Growth - Dynamics, Processes, Cells | Britannica
    Growth - Dynamics, Processes, Cells: The mathematical analysis of the rate of growth has been a subject of interest for many years It is based on the rule of cell division: one cell gives rise to two daughter cells Hence, the theoretical increase in cell number would be a geometric series, in which one cell produces two cells, then four, eight, 16, and so on In reality, however, the rate of
  • Zoology | Definition, History, Examples, Importance, Facts | Britannica
    Zoology, branch of biology that studies the members of the animal kingdom and animal life in general It includes both the inquiry into individual animals and their constituent parts, even to the molecular level, and the inquiry into animal populations, entire faunas, and the relationships of
  • Lipid | Definition, Structure, Examples, Functions, Types, Facts . . .
    Lipid, any of a diverse group of organic compounds including fats, oils, hormones, and certain components of membranes that are grouped together because they do not interact appreciably with water


















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