• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

The aim of the experiment is to determine the effect of temperature variation on the rate of an enzyme reaction. We choose hydrogen peroxide as substrate, and catalyse as the enzyme.

Extracts from this document...

Introduction

THE EFFECT OF TEMPERATURE VARIATION ON THE RATE OF AN ENZYME REACTION Aim: The aim of the experiment is to determine the effect of temperature variation on the rate of an enzyme reaction. We choose hydrogen peroxide as substrate, and catalyse as the enzyme. The latter ingredient is contained in potatoes. In fact, equally sized pieces of potato are involved in the experiment. The following equation predicts the outcome of the reaction between the mentioned reagents: Hydrogen peroxide + catalyse = water + oxygen We measure the rate of reaction by observing the amount of oxygen given off. List of equipment: The apparatus employed in experiment consists of the following items: * Beakers * Thermometer: to measure the temperature of the substrate * Stop clock * Delivery tube: the oxygen given off will travel through this tube * Potato: enzyme catalyse is contained in the potato * Hydrogen peroxide: substrate * Bunsen burner: to heat up the hydrogen peroxide at the chosen temperatures * Seringe : to suck up a particular amount of the substrate, so each test tube has the same amount of substrate. * Test tubes Method: The experiment involves an enzyme found in all living cells, catalyse, causing hydrogen peroxide to decompose into water and oxygen. The main response variable we observe is the rate of the reaction, as reflected by the amount of oxygen released. This we measure with the aid of a delivery tube, that is, by counting the number of oxygen bubbles coming out of the tube. The greater the count, the faster the reaction. ...read more.

Middle

This is, indeed, the reason why few cells can tolerate higher temperatures than approximately 45�C. The mechanism of heat-induced structural denaturation of the enzyme is well understood at a molecular level. The heat breaks the hydrogen bonds between distant parts of the polypeptidic chain of the enzyme, so that the protein loses stability of its three-dimensional conformation. Because such stability is so essential to chemical function, any temperature increase resulting in a structural collapse of the protein will reduce or totally block the enzymatic activity. Therefore I predict that heating the Hydrogen peroxide beyond a certain temperature threshold will gradually kill the experiment reaction. Fair test: To make the test fair, the following parameters must remain constant during the course of the experiment: (1) the amount of water in the beaker, (2) the amount of Hydrogen Peroxide and Catalyse, (3) the duration of reaction , and (4) if possible the room temperature. It is very hard to keep the room temperature constant, since the experiment will be run during different days, and it is very likely to have a change of temperature during the intervals of time between one day and another. If the reaction happens too quickly, I will have to dilute the substrate, to balance out the reaction. I will report accurate results, in order to insure that the test is done fairly. Experimental results A result table of the No. of bubbles given off at different temperatures Temperature (�C) ...read more.

Conclusion

For all the other parts of the experiment I have tried to be as fair as possible: the amount of potato put in the tube was cut with the same size instrument all the time, the potato had been conserved in a suitable place for the whole duration of the experiment, so the enzyme inside it would not get denatured. I didn't gain any anomalous results from the experiment, apart from in the first attempt at it, when the range of temperatures didn't give a clear enough idea of the pattern the reaction was taking. To improve my method, I could be more precise on the counting of oxygen given off from the reaction. I could use a measuring cylinder to get the amount of oxygen given off in ml, which would be certainly more accurate then me counting the bubbles given off. I could investigate further how the enzyme's rate of reaction varies with temperatures below 20�C. I already know that at low temperatures enzyme's have a slow rate of reaction, but my curve would be more complete, and my theory would be clearer. I would have as my minimum temperature 0�C and a range of temperatures that would go up to 50�C in fives, keeping the condition of experiment as constant as possible. I can also repeat my experiment many times in order to measure the variability between experiments. Despite this I consider my results clear enough to prove my beginning prediction. ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our GCSE Patterns of Behaviour section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related GCSE Patterns of Behaviour essays

  1. The aim of the investigation is to examine the kinetics involved in the reactions ...

    This was overcome by holding the boiling tubes upright. Source of Error Calculation % Error Magnesium ribbon [1/20] x 100 5.00 Volume of acid [0.05/10.0] x 100 0.50 Concentration of acid [0.01/1.00] x 100 1.00 Thermometer [0.05/25] x 100 2.00 Total 8.50% The total percentage error = 8.50% approximately Percentage errors for the activation energy The activation energy can

  2. Investigation on the effect of temperature on enzyme reaction

    will be needed for this experiment. Variables In order for the experiment to be successful, some things need to be kept the same and some need to be changed. The method has to be kept the same and the concentration of the enzyme also will be kept the same.

  1. Factors Affecting Enzyme Activity

    I think there will be a relationship of proportionality between the concentration of the suspension and the rate of reaction. Below is a predicted graph of results (all measurements are in arbitrary units). I have plotted all five graphs on one set of axes as this will make my results easier to analyse once I have collected them.

  2. Find out how the rate of hydrolysis of an organic halogen compound depends on ...

    Bond breaking is an endothermic process. A pair of reacting molecules must have enough energy between them to pass over the activation enthalpy barrier before a reaction can occur. If the energy barrier is very high, relatively few pairs of molecules will have enough energy to overcome it and react to form the products - so the reaction is slow.

  1. Enzymes - show how substrate concentration affects the rate of reaction for an enzyme ...

    5.882352941% (Percentage error of burette) = 10 Therefore the percentage error given by the burette will be 10 times less than the percentage error given by the measuring cylinder when collecting oxygen. As result of this I will be using a burette to collect the volume of oxygen as a burette will provide more accurate results.

  2. Investigation On The Enzyme Trypsin

    not compensate for the fact that the temperature had risen, so the molecules would be moving faster, hence more collisions would take place (and more achieving the activation energy required), and this would result in a faster rate of reaction.

  1. THE EFFECT OF BILE SALT ON THE ACTION OF THE ENZYME LIPASE

    Volume of lipase Increasing the volume of lipase will result in an increase in the rate of reaction as more frequent collisions will occur between the substrate (lipid) and enzyme (lipase), as the substrate molecules will bind to active site of lipase more often.

  2. The Effect of Catalase in the Breakdown of Hydrogen Peroxide

    It can also interfere with chemical reactions. * When the experiment is complete and equipment and spillages are taken care of, hands must be washed thoroughly. The Preliminary Experiment: I tried to test the outcome of the enzymes present in peeled potato and unpeeled potato at different percentages.

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work