September 19, 2012
Olivia DePhillips
Lab Partner: Joy Morgan Meyers
Signature:
Introduction Enzymes are biological molecules that catalyze chemical reactions. In enzymatic reactions, the molecules at the beginning of the process, called substrates, are converted into different molecules, called products. Almost all chemical reactions in a biological cell need enzymes in order to occur at rates sufficient for life. Like all catalysts, enzymes work by lowering the activation energy for a reaction, thus dramatically increasing the rate of the reaction. As a result, products are formed faster and reactions reach their equilibrium state more rapidly. Most enzyme reaction rates are millions of times faster than those of comparable un-catalyzed reactions. As with all catalysts, enzymes are not consumed by the reactions they catalyze, nor do they alter the equilibrium of these reactions. However, enzymes do differ from most other catalysts in that they are highly specific for their substrates. Enzymes are known to catalyze about 4,000 biochemical reactions.
This activity/lab displays how enzymes work, and shows the effects of different substrate concentrations on the rate of enzyme activity. The toothpickase will break toothpicks as instructed, while the time keeper watches the clock. This breaking of toothpicks in a set amount of time represents how enzymes speed up reactions. We hypothesize that the toothpickase’s rate of activity will be higher when the toothpicks are more concentrated, as opposed to when they are less concentrated. If the toothpickase’s rate of activity is higher when the toothpicks are more concentrated, then enzymes work faster when substrates are more concentrated.
Materials 1. Two groups of 50 toothpicks, and one group of 35 toothpicks 2. One pencil per person 3. A watch or clock with easy access 4. One plastic bag 5. One lab packet per person 6. One calculator