The Online Encyclopedia and Dictionary






Vascular plant

The vascular plants are those plants that have specialized cells for conducting water and sap within their tissues, including the ferns, clubmosses, horsetails, flowering plants, conifers and other gymnosperms, but not mosses, algae, and the like (nonvascular plants). They are set apart in two important ways:

  1. Vascular plants have water-carrying tissues, termed tracheids, in their tissues, enabling the plants to evolve larger and more elaborate structures, while non-vascular plants lack these and are restricted to relatively small sizes.
  2. In vascular plants, the principal generation phase is the sporophyte, which is diploid with two sets of chromosomes per cell. In non-vascular plants, the principal generation phase is often the gametophyte, which is haploid with one set of chromosomes per cell. See also alternation of generations.

Vascular plants are occasionally grouped as a single division (Tracheophyta) or subkingdom (Tracheobionta), but neither is very common and both conflict with other common systems.

Capillary action and transpiration work to allow xylem carry water and sap upward toward the leaves from the roots, while the phloem tissue carries organic nutrients throughout the plant.

In addition to this, there are vascular tissues. A vascular tissue is composed of xylem of phloem, this tissue can give the plant more strengh.

A vascular bundle is groups of xylem, phloem and cambium cells in stems of plants descended from the procambium embryonic tissue layer.

Vascular cambium is a layer of lateral meristematic tissue between the xylem and phloem in the stems of woody plants. Lateral meristem tissue in plants that produces secondary growth.

Vascular cylinder is a central column formed by the vascular tissue of a plant root; surrounded by parenchymal ground tissue.

Vascular parenchyma is Specialized parenchyma cells in the phloem of plants.

Vascular plants is a group of plants having lignified conducting tissue (xylem vessels or tracheids).

Vascular system is Specialized tissues for transporting žuids and nutrients in plants; also plays a role in supporting the plant; one of the four main tissue systems in plants.


See also

Last updated: 06-02-2005 13:46:10
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