Stele (biology)

Central part of a root or stem

In a vascular plant, the stele (also called vascular stele or vascular cylinder) is the central part of the root or stem containing the tissues derived from the procambium. These include vascular tissue, in some cases ground tissue (pith) and a pericycle, which, if present, defines the outermost boundary of the stele. Outside the stele lies the endodermis, which is the innermost cell layer of the cortex.

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