tracheid, in botany, primitive element of xylem (fluid-conducting tissues), consisting of a single elongated cell with pointed ends and a secondary, cellulosic wall thickened with lignin (a chemical binding substance) containing numerous pits but having no perforations in the primary cell wall.

What are tracheids and xylem vessels?

Tracheids and vessels are the components of the complex xylem tissue. Both help in conduction of water along the stem and provide mechanical support to the plant. Both cells are tubular. Secondary lignification is present in both cells. They become dead on maturity.

What is tracheids and its function?

Tracheids are the water-conducting and mechanical supporting cells of gymnosperms; water is transported longitudinally through endplates and laterally through pits (a). Angiosperm vessels function primarily to transport water and are individually shorter than tracheids (b).