| 释义 |
tracheid Bot.|ˈtreɪkiː-, trəˈkiːɪd|
Also -ide.
[a. Ger. tracheïde, introduced 1863 by Sanio Bot. Zeitung 113 ‘cellulae sive fibrae ligneae tracheïdeae, kurzweg Tracheïdzellen oder Tracheïden’: f. trachea + -ide, -id2.]
A vascular cell, with pitted lignified wall, which serves for the conduction of water; a vascular wood-cell.
The wood of the vascular tissue of Gymnosperms and Vascular Cryptogams consists wholly of tracheids.
1875Bennett & Dyer Sachs' Bot. 98 To the Vascular forms belong the ducts and the vascular wood-cells or Tracheïdes. Ibid. 99 Vessels with prosenchymatous constituents now form the immediate passage to the vascular wood-cells (Tracheïdes). 1885G. L. Goodale Physiol. Bot. §266. 82 Cells..which are closed throughout..are known as Tracheids. 1895Oliver tr. Kerner's Nat. Hist. Plants I. 276 The walls of the wood-vessels exhibit similar thickenings to those of the wood-cells or tracheides. 1907D. P. Penhallow Man. N. Amer. Gymnosperms vi. 88 Such tracheids are invariable features of the ray in all the higher Coniferæ. 1910J. M. Coulter et al. Textbk. Bot. I. iv. 241 Tracheids are single cells thus formed. 1948[see collapse n. 4]. 1974Sci. Amer. Apr. 59/1 Tracheids predominate in softwoods, which have no vessel cells or libriform fiber cells.
Hence tracheidal |treɪkiːˈaɪd(ə)l, trəˈkiːɪd(ə)l| a., pertaining to or of the nature of a tracheid.
1891in Cent. Dict. |