Tracheid
Definition
The primary water-conducting and mechanical cell of softwoods (conifers). Elongated, pointed at both ends, and lacking a perforation plate: water passes through pit pairs in the wall rather than through an open lumen. Tracheids also appear in some hardwoods.
- Primary in
- Softwoods (conifers), all vascular plants
- Cell shape
- Elongated, pointed at both ends
- Wall type
- Thick, pitted, or spiral-thickened secondary walls
Common questions
What is a tracheid and what does it do?+
A tracheid is a water-conducting cell found in the xylem of plants. It has thick secondary walls with characteristic pits or spiral thickening that give it both strength and function. Tracheids move water and minerals throughout the plant while also providing structural support.
How do tracheids move water differently than other plant cells?+
Unlike vessel cells in hardwoods, tracheids lack an open perforation plate. Instead, water flows between adjacent cells through pit pairs in their walls. This design is common in softwoods like conifers but can also appear in some hardwood species.
Why are tracheids useful for wood identification?+
The wall patterns of tracheids are key diagnostic features in wood anatomy. The size, shape, and arrangement of pits and wall thickening vary by tree species, making them reliable markers for distinguishing wood types under a microscope.
Related terms
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- Parenchyma
- Thin-walled, roughly spherical or elongated cells that form the bulk of soft plant tissues, including the leaf mesophyll. They are the most...
- Ray
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- Ring-porous
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- Sclerenchyma
- A plant tissue composed of thick-walled, lignified cells including fibres and stone cells (sclereids). Sclerenchyma cells are physically resistant to digestion and...
- Trichome
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- Vessel element
- A wider, shorter water-conducting cell found in hardwoods (flowering plants). Vessel elements join end-to-end through perforations to form vessels. Their arrangement, diameter,...
- Vessel (pore)
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Explained in these topics
- Plant Anatomy and Morphology for IdentificationA water-conducting cell with thick, pitted, or spiral-thickened secondary walls. Common in softwoods (conifers) and in the xylem of all vascular plants. Trache...
- Wood Anatomy and Microscopic IdentificationThe primary water-conducting and mechanical cell of softwoods (conifers). Elongated, pointed at both ends, and lacking a perforation plate: water passes throug...