Question 1 answer: Koch's postulates are a series of ground rules to determine whether a given organism can cause a given disease. , who developed a logical series of observations and experiments (Koch’s postulates) that proved the specific element of many infectious diseases, starting with anthrax. The series of steps worked out by Koch and others has become known as Koch’s postulates. He completed the famous postulates with anthrax. We instead use the Koch postulates because it is the best time-tested models for determining specific cause-and-effect in bacteriology. mpkb.org/home/pathogenesis/kochs_postulates Question 2 answer: Starch, glycogen, dextran and cellulose are all polymers of glucose. They differ in the type of glucose present and the bonds which link the glucose monomers together. Starch and glycogen are made from alpha-glucose. This is an isomer of glucose in which the hydroxyl (-OH) group attached to carbon number 1 is below the plane of the ring. Starch is itself composed of two types of polymer:amylose and amylopectin. In amylose, the glucose monomers are linked by 1,4 glycosidic bonds. This means that the bond connects carbon atom number 1 in one glucose to carbon atom number 4 in the other glucose. This produces an unbranched chain of glucose which then folds up to form a coil or helix. Dextran, is a slime layers of glucose polymer which bacteria secretes, and this substance causes sticky layer to develop on teeth that leads to plaque. Glycogen is similar in structure to amylopectin, but branches more frequently. Cellulose is an unbranched polymer composed of beta glucose molecules. Beta glucose is an isomer of glucose in which the hydroxyl group attached to carbon 1 is above the plane of the ring. The glucose monomers are linked by 1,4 glycosidic bonds.
Why can’t an enzyme that hydrolyzes starch degrade cellulose? Enzymes are chemicals