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In a vascular plant, the stele is the central part of the root or stem containing the vascular tissue and occasionally a pith. The concept of the stele was developed in the late nineteenth century by P. E. L. van Tieghem as a model for understanding the relationship between the shoot and root, and for discussing the evolution of vascular plant morphology. Now, at the beginning of the twenty-first century, plant molecular biologists are coming to understand the genetics and developmental pathways that govern tissue patterns in the stele. Divisions Non-seed-bearing plants Equisetophyta Lycopodiophyta Psilotophyta Pteridophyta Superdivision Spermatophyta Pinophyta Cycadophyta Ginkgophyta Gnetophyta Magnoliophyta The vascular plants are plants in the Kingdom Plantae (also called Viridiplantae) that have specialized tissues for conducting water. ...
ROOT is an object-oriented software package developed by CERN. It was originally designed for particle physics data analysis and contains several features specific to this field, but it is also commonly used in other applications such as astronomy and data mining. ...
A stem is the main axis of a vascular plant that is divided into nodes and internodes and has one or more leaves or buds at the nodes. ...
Cross section of celery stalk, showing vascular bundles, which include both phloem and xylem. ...
The centre dark spot (about 1 mm diameter) in this yew wood is the pith Pith is a light substance that is found in vascular plants. ...
In botany, a shoot is more or less synonamous with the term stem For biological and botanical definitions and information, see the main article on stems Shoots function in providing an axis for buds, fruits and leaves. ...
ROOT is an object-oriented software package developed by CERN. It was originally designed for particle physics data analysis and contains several features specific to this field, but it is also commonly used in other applications such as astronomy and data mining. ...
Plant anatomy - a field of botany which deals with structure and function of plant tissues and cells. ...
Protosteles
The earliest vascular plants had both root and shoot with a central core of vascular tissue. This consisted of xylem in the center, surrounded by a region of phloem tissue. Around these tissues there might be an endodermis that regulated the flow of water into and out of the vascular core. Such an arrangement is termed a protostele. Divisions Non-seed-bearing plants Equisetophyta Lycopodiophyta Psilotophyta Pteridophyta Superdivision Spermatophyta Pinophyta Cycadophyta Ginkgophyta Gnetophyta Magnoliophyta The vascular plants are plants in the Kingdom Plantae (also called Viridiplantae) that have specialized tissues for conducting water. ...
It has been suggested that Vessel element be merged into this article or section. ...
In vascular plants, phloem is the living tissue that carries organic nutrients, particularly sucrose, to all parts of the plant where needed. ...
Endodermis is the bottom layer of skin. ...
There are three basic types of protostele:
- haplostele - the most basic of protosteles, with a cylindrical core of vascular tissue. This type of stele is the most common in roots.
- actinostele - a variation of the protostele in which the core is lobed. This type of stele is rare among living plants, but is found in stems of the whisk fern, Psilotum.
- plectostele - a protostele in which interconnected plate-like regions of xylem are surrounded and immersed in phloem tissue. Many modern club mosses (Lycopodiopsida) have this type of stele within their stems.
Species Psilotum nudum (L.) Beauvois Psilotum complanatum Sw. ...
Families Lycopodiaceae Huperziaceae The Class Lycopodiopsida includes the clubmosses. ...
Image File history File links Protostele. ...
Siphonostele Plants that produce complex leaves also produce more complex stelar arrangements. The hormones produced by the young leaf and its associated axillary bud affect the development of tissues within the stele. These plants have a pith in the center of their stems, surrounded by a cylinder containing the vascular tissue. This stelar arrangement is termed a siphonostele. The leaves of a Beech tree A leaf with laminar structure and pinnate venation In botany, a leaf is an above-ground plant organ specialized for photosynthesis. ...
A hormone (from Greek horman - to set in motion) is a chemical messenger from one cell (or group of cells) to another. ...
It has been suggested that this article or section be merged into Plant stem. ...
The centre dark spot (about 1 mm diameter) in this yew wood is the pith Pith is a light substance that is found in vascular plants. ...
There are three basic types of siphonostele:
- solenostele - the most basic of siphonosteles, with a central core of pith enclosed in a cylinder of vascular tissue. This type of stele is found in whisk ferns and lycophytes today.
- dictyostele - a variation of the solenostele caused by dense leaf production. The closely arranged leaves create multiple gaps in the stelar core. Among living plants, this type of stele is found only in the stems of ferns.
- eustele - the most common stelar arrangement in stems of living plants. Here, the vascular tissue in arranged in vascular bundles, usually in one or two rings around the central pith. In addition to being found in stems, the eustele appears in the roots of monocot flowering plants.
Siphonosteles may be ectophloic, with the phloem tissue positioned on one side of the xylem and closer to the epidermis. They may also be amphiphloic, with the phloem tissue on both sides of the xylem. Among living plants, many ferns and some Asterid flowering plants have an amphiphloic stele. Ferns could be the plural of fern, a type of plant that reproduces using spores rather than seeds. ...
Cross section of celery stalk, showing vascular bundles, which include both phloem and xylem. ...
ROOT is an object-oriented software package developed by CERN. It was originally designed for particle physics data analysis and contains several features specific to this field, but it is also commonly used in other applications such as astronomy and data mining. ...
Orders Base Monocots: Acorus Alismatales Asparagales Dioscoreales Liliales Pandanales Family Petrosaviaceae Commelinids: Arecales Commelinales Poales Zingiberales Family Dasypogonaceae Monocotyledons or monocots are a group of flowering plants usually ranked as a class and once called the Monocotyledoneae. ...
Image File history File links Siphonostele. ...
In the APG and APG II system for classification of angiosperms, the names eudicots or tricolpates are applied to a clade, a monophyletic group. ...
There is also a variant on the eustele found in monocots like maize and rye. The variation has numerous scattered bundles in the stem and is called an atactostele. However, it is really just a variant of the eustele. Binomial name Zea mays L. Maize (Zea mays ssp. ...
Binomial name Secale cereale M.Bieb. ...
Solenostele:
its derived from siphonostele siphonostele + 1 gap = solanostele solanostele condition is seen in case of megaphyllous leaves
gaps are formed as the large leaves require vascular supply so the vascular supply is diverted to meet the growing requirements of the plant
solanostele can be of Ectophleoic or amphiphloeic types
solanosteleic condition is seen in case of Marsilea
See also Cross section of celery stalk, showing vascular bundles, which include both phloem and xylem. ...
Cross section of celery stalk, showing vascular bundles, which include both phloem and xylem. ...
References - Gifford, Ernest M. & Foster, Adriance S. (1988). Morphology and Evolution of Vascular Plants, (3rd ed.). New York: W. H. Freeman and Company. ISBN 0-7167-1946-0.
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