Enzymes speed up reactions. They have an area with a very particular shape called the ‘active site’. When the right molecule comes along (substrate molecule) it will fit perfectly into the active site and there will be a reaction. After the reaction the products then leave the active site. This process is often referred to as the lock and key theory as only one enzyme can carry out one type of reaction.
The catalase enzyme speeds up the breakdown of hydrogen peroxide into oxygen and water. The hydrogen peroxide molecule acts as the substrate molecule and enters the active site where it is broke down into oxygen and water. The oxygen and water then leave the active site. Catalase enzyme Hydrogen peroxide (toxic) oxygen + water In the investigation I am doing, these are the factors I could change: * The concentration of the enzyme * Increase the temperature * Increase the PH I have chosen to investigate how the concentration of the enzyme affects the rate of reaction. I expect that the more concentrated the enzyme the faster the reaction time will be. Changing the concentration of the enzyme will affect the rate of the reaction. I predict that as we increase the concentration of the enzyme the faster the rate of reaction will be. I think this because as you add more catalase, the catalase will be able to break down more hydrogen peroxide molecules because there will be more active sites, however there will be a point where increasing the concentration of enzymes will be pointless as there will already be the same amount of active sites as hydrogen peroxide molecules. I predict that the rate of reaction with 20 catalase will be double that of 10 catalase because if you have double the catalase then they will digest the hydrogen peroxide twice as quick. Equipment * Small measuring cylinder 100ml * Pipette *