| 释义 |
symplast Bot.|ˈsɪmplɑːst, -æ-|
[f. sym- + -plast.]
†a. [ad. G. symplast (J. von Hanstein 1880, in Bot. Abh. IV. ii. 9).] A multinucleate cell created either by the fusion of cells into one cytoplasmic mass, or by the division of the nucleus of a single energid. Obs.
1894Jrnl. R. Microsc. Soc. 376 Klemm objects to the term ‘unicellular’ as applied to Caulerpa prolifera and similar organisms. They should be regarded rather as ‘symplasts’, composed of a number of energids. 1900Ibid. 475 When the polyplasts are so completely fused together that their cytoplasms form a single mass in which a number of nuclei are imbedded, Hanstein's term ‘symplasts’ may be applied. 1912L. A. Borradaile Man. Elem. Zool. vi. 116 Groups of similar, unseparated energids are known as syncytia. They may be plasmodia, formed by the union of free energids, or symplasts, formed by the division of the nucleus of a single energid.
b. [ad. G. symplast (E. Münch Die Stoffbewegungen in der Pflanze (1930) 73).] A continuous network of interconnected plant cell protoplasts.
1938Amer. Jrnl. Bot. XXV. 529/2 Studies on the occurrence of plasmodesmata in living tissues show that where pits occur the protoplasts are commonly connected by these strands. Consequently the ‘symplast’..of the root must constitute an interconnected protoplasmic unit. 1976B. E. S. Gunning in Gunning & Robards Intercellular Communication in Plants: Studies on Plasmodesmata i. 2 Following the evolution of plasmodesmata, the plant body is..composed of two major compartments, for which the terms apoplast and symplast are convenient (Münch, 1930)... The term symplast refers to the interconnected protoplasts, all bounded by a continuous plasmalemma.
Hence symˈplastic a., of or pertaining to a symplast or symplasm; symplastic growth, the expansion of a common wall between adjacent plant cells during cell enlargement.
1916[see symplasm a]. 1930J. H. Priestley in New Phytologist XXIX. 132 It is proposed to call this alternative method of growth now described symplastic growth. 1981J. R. Barnett Xylem Cell Devel. ii. 63 This symplastic growth hypothesis..could not explain satisfactorally the type of growth in which an enlarging cell, such as a fibre, increases the number of cells with which it is in contact as it grows. |