The number of xylem groups is fairly large and the development of the xylem is from the pericycle towards the centre of the stele.
The arrangement of the xylem and the phloëm is different from that of the stem.
xylem, zī′lem, n. the woody part of vegetable tissue—opposed to the phlom, or bast part.
This shows a number of white bars (xylem) surrounded by a more delicate tissue (phloem).
The larger bundles are normal in every way, while in the smaller ones the xylem elements are considerably reduced.
These vessels together with the numerous small thick-walled cells lying between the pitted vessels constitute the xylem.
The central tissue (x) is called the woody tissue (xylem); the outer, the bast (phloem).
The larger vascular bundles consist of xylem and phloëm surrounded by a bundle sheath of a single layer of cells.
Just above the xylem there is a group of large and small thin-walled cells.
All round the xylem and the phloëm there are many thick-walled cells.
"woody tissue in higher plants," 1875, from German Xylem, coined from Greek xylon "wood," of unknown origin.
A tissue in vascular plants that carries water and dissolved minerals from the roots and provides support for softer tissues. Xylem consists of several different types of cells: fibers for support, parenchyma for storage, and tracheary elements for the transport of water. The tracheary elements are arranged as long tubes through which columns of water are raised. In a tree trunk, the innermost part of the wood is dead but structurally strong xylem, while the outer part consists of living xylem, and beyond it, layers of cambium and phloem. See more at cambium, capillary action. Compare phloem.