BIOCHEMISTRY A  B  C  D  E  F  G  H  I  J  K  L  M  N  O  P  Q  R  S  T  U  V  W  X  Y  Z                    HOME ABOUT CATEGORIES SITE MAP COPYRIGHT ADVERTISE CONTACT entire Web this site cellulose A polysaccharide that is the main constituent of the cell wall in all green plants and most bacteria. Cellulose is the most abundant compound on Earth that is manufactured by living things. Cellulose and starch are both made from glucose monomers but there is a crucial difference between them. The monomer in cellulose is beta-D-glucose and the chemical link between these monomers is called a beta acetal linkage. As a result of the bond angles in the beta acetal linkage, cellulose is mostly a linear chain. By contrast, the bond angles of the alpha acetal linkage found in starch gives rise to a spiral structure like a coiled spring. This difference in acetal linkages has a profound effect on digestibility. Humans are unable to digest cellulose because the appropriate enzymes to breakdown the beta acetal linkages are lacking in our bodies. Undigestible cellulose is the fiber which aids in the smooth working of the intestinal tract. Animals such as cows, horses, sheep, termites, and soil bacteria, however, possess the necessary enzymes to digest cellulose. When processed cellulose is used in many different ways: wood for building; paper products; cotton, linen, and rayon for clothes; nitrocellulose for explosives; cellulose acetate for films. Related category    • BIOCHEMISTRY Also on this site: Encyclopedia of Alternative Energy & Sustainable Living Encyclopedia of History Transport Concepts & Designs (partner site) BACK TO TOP