The plant cell wall is the major determinant of the plant cell’s shape and size. Furthermore,
the cell wall also provides a defensive barrier, anchorage for the cytoskeleton, fulfils
functions in cell recognition, growth and differentiation. The wall is highly organized and is
made up of polysaccharides, proteins and various aromatic compounds which cross-link the
polymers together to provide structural support. Cellulose fibers are embedded in a hydrogel
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of matrix polysaccharides and small amounts of protein. The exact chemical composition of
the wall varies considerably from species to species and between different plant organs in
the same plant, but the basic design of the wall is consistent. The primary cell walls of dicots
contain approximately 30% cellulose, 30% hemicellulose, 35% pectin with 1-5% protein (on
a dry weight basis) compared to monocots that contain approximately 25% cellulose, 55%
hemicellulose and 10% pectin2,3.