Ashley Cottrell 10th November, 2002
Effect of Temperature on Rate of Reaction of catalase
Introduction
This investigation was in an attempt to try to find out how varying the temperature can affect an enzyme. The enzyme used was catalase which breaks down Hydrogen Peroxide, this gives off water and oxygen as effervescence. This effervescence is what is used to measure the reaction rate of the catalase. The optimal heat for enzyme activity is proven to be 37oC as anything above this denatures the enzyme. Denaturing is where the heat energy of breaks down the di-sulphide, ionic and hydrogen bonds that hold the tertiary structure together, this in turn changes the shape of the active site and so halts any reactions that the enzyme would otherwise be able to catalyze.
Method
6 test tubes were set up and 2cm squared of Hydrogen Peroxide was placed in each tube. Each tube was then placed in a water bath of the corresponding temperature (20oC, 40oC, 60oC and 80oC), and one in a beaker of ice (0oC). They were all left in for 10 minutes to take them all to the desired temperature before the experiment began.6 strips of potatoes were then cut to 1cm3 using a ruler and scalpel. One of the strips was put into each tube and then timed with a stop clock and the level of froth was measured as it rose up the side of the tube every 20 seconds until the froth started to fall. This was done to each tube individually so that a more accurate measurement was taken.
