DICT.TW Dictionary Taiwan

 cell theory 名詞
 細胞學說,胞腔理論

 Cel·lu·lar a.
 1. Consisting of, or containing, cells; of or pertaining to a cell or cells.
 Cellular plants, Cellular cryptogams Bot., those flowerless plants which have no ducts or fiber in their tissue, as mosses, fungi, lichens, and algæ.
 Cellular theory, or Cell theory Biol., a theory, according to which the essential element of every tissue, either vegetable or animal, is a cell; the whole series of cells having been formed from the development of the germ cell and by differentiation converted into tissues and organs which, both in plants and animals, are to be considered as a mass of minute cells communicating with each other.
 Cellular tissue. (a) Anat. See conjunctive tissue under Conjunctive. (b) Bot. Tissue composed entirely of parenchyma, and having no woody fiber or ducts.
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 Cell n.
 1. A very small and close apartment, as in a prison or in a monastery or convent; the hut of a hermit.
    The heroic confessor in his cell.   --Macaulay.
 2. A small religious house attached to a monastery or convent. “Cells or dependent priories.”
 3. Any small cavity, or hollow place.
 4. Arch. (a) The space between the ribs of a vaulted roof. (b) Same as Cella.
 5. Elec. A jar of vessel, or a division of a compound vessel, for holding the exciting fluid of a battery.
 6. Biol. One of the minute elementary structures, of which the greater part of the various tissues and organs of animals and plants are composed.
 Note: ☞ All cells have their origin in the primary cell from which the organism was developed. In the lowest animal and vegetable forms, one single cell constitutes the complete individual, such being called unicelluter orgamisms. A typical cell is composed of a semifluid mass of protoplasm, more or less granular, generally containing in its center a nucleus which in turn frequently contains one or more nucleoli, the whole being surrounded by a thin membrane, the cell wall. In some cells, as in those of blood, in the amœba, and in embryonic cells (both vegetable and animal), there is no restricting cell wall, while in some of the unicelluliar organisms the nucleus is wholly wanting. See Illust. of Bipolar.
 Air cell. See Air cell.
 Cell development (called also cell genesis, cell formation, and cytogenesis), the multiplication, of cells by a process of reproduction under the following common forms; segmentation or fission, gemmation or budding, karyokinesis, and endogenous multiplication. See Segmentation, Gemmation, etc.
 Cell theory. Biol. See Cellular theory, under Cellular.

 cell theory
      n : (biology) the theory that cells form the fundamental
          structural and functional units of all living organisms;
          proposed in 1838 by Matthias Schleiden and by Theodor
          Schwann [syn: cell doctrine]