ABSTRACT
This chapter deals with materials that are alive or once were alive. The general chemical groups that constitute animals and plants are the same on the macrolevel. However, the two classifications do differ in the major building material. Animals have as their basic building material proteins, while plants have as their basic building material polysaccharides. All of the basic building and genetic materials are polymeric. Since natural polymers are typically regenerable or renewable resources, nature continues to synthesize them as we harvest them. Many natural polymers are available in large quantities. For instance, cellulose makes up about one-third of the bulk of the entire plant kingdom, being present in corn stocks, tree leaves, grass, and so on. Natural feedstocks must serve many human purposes. Carbohydrates as raw materials are valuable due to their actual or potential value.
