- the solid stele of most roots, having a central core of xylem enclosed by phloem.
Origin of protostele
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for protostele
In its simplest form (as in fig. 36) it is called a protostele, and is to be found in both living and fossil plants.
In the Coal Measure period, however, the protostele was characteristic of one of the two main groups of ferns.
- a simple type of stele with a central core of xylem surrounded by a cylinder of phloem: occurs in most roots and the stems of ferns, etc
- The most primitive form of stele, consisting of a solid core of xylem encased by phloem or of xylem interspersed with phloem. The roots of all vascular plants, as well as the stems of lycophytes, have protosteles.
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