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Vascular tissue is a complex conducting tissue, formed of more than one cell type, found in vascular plants. The primary components of vascular tissue are the xylem and phloem. These two tissues transport fluid and nutrients internally. There are also two meristems associated with vascular tissue: the vascular cambium and the cork cambium. All ...
In woody plants, it forms a cylinder of unspecialized meristem cells, as a continuous ring from which the new tissues are grown. Unlike the xylem and phloem, it does not transport water, minerals or food through the plant. Other names for the vascular cambium are the main cambium, wood cambium, or bifacial cambium.
The xylem consists of vessels in flowering plants and of tracheids in other vascular plants. Xylem cells are dead, hard-walled hollow cells arranged to form files of tubes that function in water transport. A tracheid cell wall usually contains the polymer lignin. The phloem, on the other hand, consists of living cells called sieve-tube members ...
When the water pressure within the xylem reaches extreme levels due to low water input from the roots (if, for example, the soil is dry), then the gases come out of solution and form a bubble – an embolism forms, which will spread quickly to other adjacent cells, unless bordered pits are present (these have a plug-like structure called a ...
In plant anatomy, there are two main types of sieve elements. Companion cells and sieve cells originate from meristems, which are tissues that actively divide throughout a plant's lifetime. They are similar to the development of xylem, a water conducting tissue in plants whose main function is also transportation in the plant vascular system. [1]
The presence of vessels in xylem has been considered to be one of the key innovations that led to the success of the flowering plants. It was once thought that vessel elements were an evolutionary innovation of flowering plants, but their absence from some basal angiosperms and their presence in some members of the Gnetales suggest that this hypothesis must be re-examined; vessel elements in ...
A vascular bundle is a part of the transport system in vascular plants. The transport itself happens in the stem, which exists in two forms: xylem and phloem. Both these tissues are present in a vascular bundle, which in addition will include supporting and protective tissues. There is also a tissue between xylem and phloem, which is the cambium.
Unlike xylem (which is composed primarily of dead cells), the phloem is composed of still-living cells that transport sap. The sap is a water-based solution, but rich in sugars made by photosynthesis. These sugars are transported to non-photosynthetic parts of the plant, such as the roots, or into storage structures, such as tubers or bulbs. [14]