Polymeric saccharides can have 10,000 or more sugar
units, four or five different sugars, and a branched structure.
The diversity that can be envisioned is huge and much
of it is actually observed. Classification of polysaccharides
differentiates homopolymers (a single sugar type)
and heteropolymers (two or more sugar types) with subtypes
reflecting linear or branched structures within each
group. Thephysical andbiological properties of eachpolymer
depend on the architecture of the molecule as well
as the enzymatic machinery available to interact with it.
Thus, cellulose, a linear β-1-4 glucose polymer is a stable,
highly organized polymer, indigestible by man, whereas
starch, its α-linked counterpart is a major food source for
all mammalian species.