Common Misconceptions 1. Metabolism is a breaking-down process (catabolism) 2. Enzymes only catalyze the breaking-down processes 3. Enzymes are only involved in the digestion of food 4. Enzymes only speed up forward reactions 5. Heating kills enzymes. 6. The rate of enzymatic reactiondecreases because enzyme molecules are used up
Things to emphasize during lesson 1. Metabolism includes both the catabolism (breaking-down processes) and anabolism (building-up processes). 2. Enzymes also catalase the building-up processes. 3. Enzymes are involved in many physiological process, eg. Photosynthesis, respiration, protein synthesis, muscle contraction, and active transport 4. They also speed up backward reactions i.e. reversible 5. Heating denatures enzymes. Enzymes are not living organisms so that they cannot be killed. 6. Enzyme molecules will not be used up in the catalytic reaction. The decrease in the enzymatic rate is due to the gradual decrease in the substrate concentration or denaturation effect of high temperature.