ABSTRACT
There are four major types of biopolymers: (1) polysaccharides, (2) proteins, (3) lipids and (4) nucleic acids. These polymers, together with their smaller fragmentary units, are all found in living systems (Chapter 11). They are fundamentally one-dimensional polymers whose chains in some cases branch or form cross-linked varieties of greater complexity. Molecular weights can reach several million, except in the lipid group where they do not exceed about 3000. All four types of biopolymer can show subtle variations of primary chemical structure and as such can act as informational molecules. The biochemical role of proteins and nucleic acids has long been recognised in this respect. Biopolymers also show many features of secondary and tertiary structure, which can be of great importance in their technological applications as well as their biochemical role.
