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Introduction

The Effect of Temperature on the Rate of Activity of the Enzyme Peroxidase Purpose The purpose of this experiment is to investigate how the increase and decrease in temperature of enzyme in degree Celsius affect the rate of enzyme activity with the substrate. More specifically, it investigates how the decomposition of 3% hydrogen peroxide, which is the substrate, is affected by the enzyme peroxidase, which is acquired from 10 equal potato slices, by the increase and decrease in temperature of the enzyme peroxidase in degree Celsius, which is controlled by using a water bath. The effect of the changes in temperature in degree Celsius is indicated by the rate of production of oxygen gas from the breakdown of 3% hydrogen peroxide by peroxidase, which is indicated through the use of the manometer and measuring the time in seconds taken for the red water in the rubber tube from the initial mark on the tube to reach a final mark on the tube, hence investigating the effect of changes in temperature on the enzyme activity. Hypothesis If the temperature of the enzyme peroxidase acquired from potato slices is increased in degree Celsius by heating up the potato slices in the water bath, then the enzyme activity, or the decomposition of 3% hydrogen peroxide by peroxidase will also increase, which will be indicated by the increase in the rate of production of the oxygen gas, measured by the manometer, and in particular, the time in seconds for the red water inside the glass tube to reach the marked distance in the glass tube. This is due to the fact as temperature increases, the kinetic energy increases, and more effective collisions of particles occur with the required activation energy and with greater force, ...read more.

Middle

Temperature (�0.5�C) Substrate Enzyme 3% Hydrogen Peroxide Potato slices (Peroxidase) 6.0 (ice) * Gas bubbles evolve slowly * 20.8 � 0.5mm layer of bubbles form on the surface of hydrogen peroxide * Floating in hydrogen peroxide * Colliding with other potato slices * Fizzing slowly 23.0 (Room temperature) * Gas bubbles evolve * 30.0 � 0.5mm layer of bubbles form on the surface of hydrogen peroxide * few slices floating * The rest of the potato slices are in contact with each other at the bottom of the test tube * Fizzing 30.0 * Gas bubbles evolve faster than at room temperature * 20.0 � 0.5mm layer of bubbles form on the surface of hydrogen peroxide * Not floating * Slices sitting at the bottom of the test tube * Fizzing 40.0 * Gas bubbles evolve faster than at room temperature * 20.2� 0.5mm layer of bubbles form immediately on the surface of hydrogen peroxide after potatoes were placed. * Some slices floating * Fizzing Analysis The mean for the time taken for the liquid in the manometer to reach 5 cm above the initial point at two different temperatures can be calculated using the following equation: Let A represent the average time for the liquid in the manometer to reach 5 cm above the initial point at 6.0�C. Let B represent the average time for the liquid in the manometer to reach 5cm above the initial point at 23�C. A = 96.5s B = 23.1s The standard deviation for the time taken for the liquid in the manometer to reach 5 cm above the initial point at two different temperatures can be calculated using the following equation: Let A represent the data for the average time taken for the liquid in the manometer to reach 5 cm above the initial point at 6.0�C. ...read more.

Conclusion

This caused the time taken for the liquid in the manometer tubing to reach 5cm above the initial point to continuously increase as time taken between each trial (the time taken to put on the tube clamp back on the rubber tube) led to decrease and escaping of the oxygen gas produced. This is evident in Table 1, where the time values measured at 6�C, for example, increased from trial 1 to 5. Due to the fact that the times taken between trials meant the escaping or decrease in the production of oxygen gas, the varying time taken between trials at four different temperatures led to greater increase in the time values in certain trials, and inconsistency in the time values in some trials. This caused the collection of inaccurate data since the time values showed inconsistency, and this led to inaccurate average time per temperature also. The continuous decrease in the production of oxygen gas, however, did not significantly affect the outcome of the experiment because by using the t-test, the significance in the first three comparisons in Figure 1 was proven, and conclusions were drawn from the data presented. This error could be improved by restarting the set-up; more specifically, using 10mL of hydrogen peroxide and 8 potato slices for each trial. Although it would take longer time, this will ensure that no oxygen gas will escape and decrease between trials, hence enhancing the collection of more accurate data. 1 Green, John, and Sadru Damji. Chemistry. Victoria: IBID P, 2001. 2 Allot, Andrew. 2007. Biology for the IB Diploma. Toronto: Oxford University Press 3 Shinmen, Yoshifumi Shinmen, Sumio Asami, Norihide Amano, Teruo Amachi, Hajime Yoshizumi, and Eiichi Kosugi. "Peroxidase and a Process of Its Preparation." Patent Storm. 9 Apr. 2008 <http://www.patentstorm.us/patents/4737460-claims.html>. 4 Allot, Andrew. 2007. Biology for the IB Diploma. Toronto: Oxford University Press ?? ?? ?? ?? ...read more.

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