Plant Cell Walls
نویسنده
چکیده
The cell wall is the strong, outermost layer of a plant cell, located external to the plasma membrane. The cell wall often far outlives the protoplast which synthesized it. In cork, for example, the wall serves its particular biological role (physical protection of a tree trunk) for many years after the death of the protoplast. However, the walls of living cells are not inert ‘boxes’ but complex and dynamic subcellular compartments that play diverse and subtle roles in plant growth, development and defence. The walls range from 0.1 to over 10 mm thick and are composed mainly of polysaccharides; they thus differ fundamentally from cell membranes, which are 5 0.01mm thick and composed of phospholipids and proteins. This article considers the cell walls of seed plants. The walls of ferns, liverworts and charophycean algae resemble those of seed plants, but have been investigated in less detail. Other algae differ widely and are not discussed here.
منابع مشابه
Plant cell walls.
Cell walls are important features of plant cells that perform a number of essential functions, including providing shape to the many different cell types needed to form the tissues and organs of a plant. Forming the interface between adjacent cells, plant cell walls often play important roles in intercellular communication. Because of their surface location, plant cell walls play an important r...
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