Introduction
An enzyme is a globular protein which functions as a catalyst that speeds up the rate of a reaction without being consumed in the reaction. An enzyme-catalyzed reaction occurs when a substance called the substrate binds onto the active site of the enzyme. This joining allows for a reduction in the activation energy and the reduction in activation energy helps the reaction to occur at a quicker rate. Enzyme reaction can be affected by some factors such as pH, temperature, substrate concentration, enzyme concentration and inhibitors. When change occurs in pH, the interaction on which the structure of an enzyme is dependent can be damaged and even denaturation is likely to happen. Also, temperature affects enzymes. When temperature increases, enzyme activity consequently increases. However, temperature above a certain point, an enzyme can be denatured. Enzyme concentration, substrate concentration and inhibitors are other factors affecting enzyme functionality. The substrate in this lab is Hydrogen Peroxide (H2O2) and the enzyme is catalase in the liver, which locates in almost all living organisms and prevents the accumulation of toxic levels of hydrogen peroxide by decomposing hydrogen peroxide to water and oxygen. (2 H2O2 → 2 H2O + O2)
Purpose
To investigate and quantify an enzymatic reaction rate
To observe how a number of variables affect the reaction rate
Method
See an attached pre-lab sheet.
Hypothesis
# | Reaction | Hypothesis | 1 | 5Ml of substrate | Since there is no substance which reacts with the substrate, no reaction occurs. | 2 | 5Ml of H2O2 + Liver | Bubbles which represent the formation of O2 will come up at a normal rate because an enzyme inside the liver and H2O2 react together and form oxygen. | 3 | 5Ml of H2O2 + used liver from #2 | The formation of bubbles will decrease if the amount of enzyme in liver decreases. Because the liver is