Hemicellulose

Any of several heteropolymers[?] (matrix polysaccharides[?]) present in almost all cell walls along with cellulose.

Their molecular weights are usually lower than that of cellulose and they have a weak undifferentiated structure compared to crystalline cellulose. But the chains form a 'ground' - they bind with pectin to cellulose to form a network of cross-linked fibres.

Hemicelluloses include xylan, glucuronoxylan, arabinoxylan, glucomannan, and xyloglucan.