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

The effects of temperature on the rate at which a substrate is broken down.

Extracts from this document...

Introduction

03/09/03 Biology coursework An experiment on the effects of temperature on the rate at which a substrate is broken down A. Prediction: This experiment is to test the effects of temperature on the rate at which catalase breaks down hydrogen peroxide into oxygen and other products. Therefore, if the temperature is increased or decreased, the rate, at which the proteins are broken down by the enzyme, will vary: faster if the temperature is increased and slower if decreased. B. Background knowledge: This prediction is based on many points. Firstly, as the enzymes are found in the human body, one can conclude that they work better at body temperature which is roughly around 40�C. However should the temperature rise, there would be more energy and so the enzymes would vibrate more. Consequently, they are more likely to collide and so attach to proteins. As a result, more proteins are broken down. Should the temperature be lowered, the enzymes would vibrate less, giving them a lesser chance of attaching to a protein. Therefore, the proteins are broken down at a slower rate. However, there is a limit to how high the temperature can increase as the enzymes will start to denature. ...read more.

Middle

E. Variables: - The temperature of the water bath was varied. - The rate at which the enzymes broke down the hydrogen peroxide changed (this is an independent variable). - The amount of potato, hydrogen peroxide stayed the same (this is a dependent variable). F. Results: The results were as follows: (* for a 20g piece of potato and the reaction timed for 3 minutes) Temperature of catalase (in �C) Amount of gas produced from reaction (in mL) 23 (or Room temperature) 0.4 0.4 30 3 3 40 3.8 3.6 50 5.4 4 60 5.8 6.8 80 4 4 The averages of the results are thus: Temperature of catalase (in �C) Amount of gas produced from reaction (in mL) 23 (or Room temperature) 0.4 30 3 40 3.7 50 4.7 60 6.3 80 4 G. Analysis of the results: The results seem to follow a certain pattern. The amount of gas produced from the reaction seems to start at a fairly low amount at room temperature. This amount increases as the temperature rises and it is at its optimum at 60�C. From then on, it falls. To illustrate this, graph 1 was drawn (see next page). ...read more.

Conclusion

At the end of a predetermined time, the gas displaced is then measured and noted. This method is effective in the sense that factors aforementioned are controlled further. For instance, when using the potato, the number of enzymes weren't the same at each experiment. In this experiment, that number is now controlled as there is always a fixed amount of catalase. Also, when using the potato, enzymes could have been lost when it was exposed to the air. In this experiment, the catalase is in powder form so none are lost. As previously calculated, the Q10 coefficients of the enzymes are more or less equal to 1.3 and most enzymes have a Q10 coefficient of 2. This could be explained by the fact that the experiment had some flaws aforementioned in this section. This could affect the prediction because, since most enzymes have a Q10 coefficient of 2, the coefficients calculated do not comply with the rule. So my prediction could be wrong. However, given these factors, the results do add up to a conclusion. Granted, the results are rudimentary (due to some of the factors previously explained) but there is a pattern: the rate does go up and having reached the optimum temperature, the rate does drop back down again. So therefore, I can conclude that temperature does affect the rate at which the substrate is broken down. ...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 Life Processes & Cells 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 Life Processes & Cells essays

  1. Marked by a teacher

    Investigating Enzymes and the effects of different variables such as temperature on how they ...

    4 star(s)

    Outlier: Conclusion From my results graph, one thing is obvious: when you increase the temperature, the rate of reaction increases until you get to 40�C onwards. I found that at 0�C the average rate of reaction was 0.3cm3/s. However at 40�C, it was 1.67cm3/s, but then at 60�C it dropped to 0.9cm3/s.

  2. Marked by a teacher

    Biology Coursework Enzymes

    4 star(s)

    is the same throughout Accuracy In order to make sure that the experiment I conduct is accurate I will take certain things into account. I will make sure that I wash all of the used equipment thoroughly after each time I use it to ensure that the apparatus is clean and will not affect my final results.

  1. Find out how a certain factor that is changed will affect the reaction rate ...

    The lower the pH, the higher the hydrogen ions in a concentration. Hydrogen ions can interact with the R groups of amino acids, affecting the way in which they bond with each other and therefore affecting their tertiary structure. The optimum pH for most enzymes is seven as it is fairly neutral conditions.

  2. Enzymes experiment. Do enzymes work faster or slower when the temperature is high?

    Hopefully this will change and it will clear out which I would then be able to get my results. I am using the protein strip because the outer layer of the protein strip it will clear out while the protease is breaking it down in the different temperatures that I

  1. HOW DOES TEMPERATURE AFFECT CATALASE ENZYMES?

    Although the enzyme obviously joins with the substrate for a short while, the enzyme and substrate split apart afterwards, releasing the enzyme. Thus the enzyme is not used up in the process (unlike the substrate(s)), so it can continue to react if more substrate is provided.

  2. Investigating the effects of temperature on an Enzyme Catalase.

    The factor I have chosen to investigate is 'Temperature'. To keep the investigation fair I am to control the variables in the following ways: * Using a pH7 buffer will control the pH; I have chosen pH7 because it is the optimum pH. * The enzyme concentration will be controlled by the amount of potato used.

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