A type of water-conducting cell in the xylem which lacks perforations in the cell wall.
- ‘The lack of lignin in lateral walls shifts the function of ‘pipe walls’ to the turgid parenchyma paving the tracheid.’
- ‘Tissues external to the xylem were removed because of the presence of large resin ducts which could release materials that would obstruct water flow through the xylem tracheids.’
- ‘Vessel elements, tracheids, fibres, sieve tube elements, sieve cells, and parenchyma cells are the major components of vascular tissue.’
- ‘Lignins occur in great quantity in the secondary cell walls of fibres, xylem vessels and tracheids.’
- ‘This method allows the cavitation resistance of the metastable liquid water in the lumen of tracheids in conifer sapwood sections to be estimated.’
Late 19th century: from German Tracheide, from medieval Latin trachea (see trachea).
We take a look at several popular, though confusing, punctuation marks.