ABSTRACT
Polysaccharides are either structural components, most notably in plant cell walls, or storage components, particularly in seeds. Glycoproteins and mucosubstances contain both polysaccharide and protein chains covalently linked together. It is important to emphasize the covalent nature of the structure, many materials which were thought to be mucosubstances have proved simply to be mixtures. Polysaccharide polydispersity is an important concept to understand when describing polysaccharides since, whereas the synthesis of proteins is precisely regulated from the gene sequence with the result having precisely defined molecular weights. The functional properties of polysaccharides are governed by their chemical nature and their physico-chemical characteristics. Electron microscopy provides us with a direct visualization of polysaccharide structure but at a price: the environment a molecule finds itself in for analysis is even more alien than that required for x-ray diffraction. Atomic force microscopy also provides us with direct visualization whilst keeping the polysaccharide in direct contact with solution.
