What is stele and types of stele?
The term stele refers to the central cylinder of vascular tissues consisting of xylem, phloem, pericycle and sometimes medullary rays with pith (Figure 2.37). There are two types of steles. 1. Protostele. 2.
What are the major function of stele?
The stele functions in the transport of water, nutrients, and photosynthates, while the cortical parenchyma fulfills metabolic functions that are not very well characterized.
What are the parts of the stele?
The stele consists of vascular tissue, ground tissue or pith, and a pericycle. The pericycle mainly forms the outermost boundary of the stele. Therefore, the stele can be explained as the vascular bundle. The stele is composed of mainly three tissues which are the pericycle, the xylem, and the phloem.
What is a stele used for?
A stela is an upright monument containing information in the form of texts, images or a combination of the two. Stelae have been used to commemorate people or events, to delineate physical spaces or as objects through which to access the dead or divine.
Which is primitive stele?
vascular plants The simplest and apparently most primitive type of stele is the protostele, in which the xylem is in the centre of the stem, surrounded by a narrow band of phloem.
What do you mean by Actinostele?
Definition of actinostele : a vascular core (as in most roots and some stems) having the xylem and phloem in alternating or radial groups within a pericycle — compare stele.
What stele morphology is characteristic of the ferns?
vascular plants The steles—cylinders of vascular tissues in the centres of fern stems—exhibit somewhat diverse patterns. Most common ferns possess a “dictyostele,” consisting of vascular strands interconnected in such a manner that, in any given cross section of stem, several distinct bundles can be observed.
What is medullary rays in plants?
Medullary rays are strips of parenchyma present between vascular bundles of dicot stem. They separate xylem and phloem bundles. They serve as a link between pith and cortex. They are also known as pith rays and vascular rays.
How many major types of stele are?
There are three basic types of protostele: haplostele (FIG. 7.32), actinostele, and plectostele (FIG. 7.33).