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A vessel element or vessel member (also called a xylem vessel) [1] is one of the cell types found in xylem, the water conducting tissue of plants. Vessel elements are found in most angiosperms (flowering plants) and in some gymnosperms such as cycads and Ephedra, but absent in conifers. Vessel elements are the main feature distinguishing the ...
The other type of vascular element, found in angiosperms, is the vessel element. Vessel elements are joined end to end to form vessels in which water flows unimpeded, as in a pipe. The presence of xylem vessels (also called trachea [30]) is considered to be one of the key innovations that led to the success of the angiosperms. [31]
Cross section of celery stalk, showing vascular bundles, which include both phloem and xylem Detail of the vasculature of a bramble leaf Translocation in vascular plants. 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 ...
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.
Organic compounds such as sucrose produced by photosynthesis in leaves are distributed by the phloem sieve-tube elements. 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.
Angiosperms have both tracheids and vessel elements. [1] A tracheid is a long and tapered lignified cell in the xylem of vascular plants. It is a type of conductive cell called a tracheary element. Angiosperms use another type of conductive cell, called vessel elements, to transport water through the xylem.
The phloem is the living portion of the vascular system of a plant, and serves to move sugars and photosynthate from source cells to sink cells. Phloem tissue is made of sieve elements and companion cells, and is surrounded by parenchyma cells. The sieve element cells work as the main player in transport of phloem sap.
According to cohesion-tension theory, water transport in xylem relies upon the cohesion of water molecules to each other and adhesion to the vessel's wall via hydrogen bonding combined with the high water pressure of the plant's substrate and low pressure of the extreme tissues (usually leaves).