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

Investigating how quickly the enzyme catalase breaksdown hydrogen peroxide.

Extracts from this document...

Introduction

Biology Coursework - Planning Investigating how quickly the enzyme catalase breaks down hydrogen peroxide I will be investigating the enzyme catalase and the factors affecting the rate at which it speeds up the breakdown of hydrogen peroxide. I will be carrying out this experiment to find out if certain factors speed up the reaction at different rates. An enzyme is a substance that acts as a catalyst in living organisms, regulating the rate at which chemical reactions take place without the enzyme being altered in the process. The name enzyme was suggested in 1867 by the German physiologist, Wilhelm Kuhne (1837 - 1900), and it comes from the Greek phrase en zyme, which means "in leaven". The biological processes that occur within all living organisms are chemical reactions and most are regulated by enzymes. Without enzymes, many of these reactions would not take place at a distinguishable rate. The faster a reaction happens, the more gas it gives off and its temperature increases. Enzymes also have valuable industrial and medical uses. The fermenting of wine, leavening of bread, curdling of cheese and brewing of beer have been practiced from earliest times, but not until the 19th Century were these reactions understood to be the result of catalytic activity of enzymes. The uses of enzymes in medicine include killing disease-causing microorganisms, promoting wound healing, and diagnosing certain diseases. ...read more.

Middle

In order to understand the experiment that I am carrying out, it is necessary that I take certain factors and variables into account. There are four possible factors affecting the reaction of hydrogen peroxide that need to be noted. For a given amount of enzyme, the rate of an enzyme-controlled reaction increases with an increase in substrate concentration. At low substrate concentrations, the active sites of the enzyme molecules are not all used - there are simply not enough substrate molecules to occupy them all. As the substrate concentration is increased, more and more sites are used. A point, however, is reached when all the active sites are occupied and the amount of enzyme is the limiting factor, as the increasing of substrate concentration cannot increase the rate of reaction. If the temperature increases, it can affect the rate of an enzyme-controlled reaction in two ways: 1) As the temperature increases, the kinetic energy of the substrate and enzyme molecules increases and so they move faster. The faster these molecules move, the more often they collide with one another and therefore the rate of reaction is faster. 2) As the temperature increases, the more the atoms, which make up the enzyme molecules, vibrate. This breaks the hydrogen bonds and other forces, which hold the molecules in their precise shape. ...read more.

Conclusion

26cm3 21cm3 300 27cm3 23cm3 Gas given off 7cm3 18cm3 From my preliminary I have discovered a few corrections that need to be made in order to perfect my plan. I will also take readings from concentrations of 5% and 15% to give me a larger range from which to draw my conclusions and I will also repeat the experiment twice or three times in order to make sure my results are reliable. I will take an average from which to plot points on my graph. I didn't repeat the experiment twice for each concentration, as I did not have enough time. In my final experiment I will make sure that I have enough time to perform the experiment slowly and carefully. I will also practice starting the stop clock at the precise moment that I put the bung in place so as to get accurate results. I can now reinforce my prediction with the results that I got from my preliminary. I predict that the 5% concentration will react slower than the 10% concentration, as there will be less substrate to make use of the active sites of the enzyme. So too, the 15% concentration will react faster than the 10% concentration but slower than the 20% concentration as it has more substrate than the 10% concentration, but less substrate than the 20% concentration to fill the active sites of the enzyme. ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our AS and A Level Molecules & 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 AS and A Level Molecules & Cells essays

  1. Marked by a teacher

    How does the concentration of enzymes affect the breakdown of starch by a-amylase in ...

    4 star(s)

    This is, however, not a major problem, as this experiment is just so that an idea is achieved of whether the concentrations are suitable or not. The table below shows the results obtained from this pilot test: Concentration of enzyme solution (%)

  2. Investigate how concentration of the enzyme catalase in celery tissue alters the rate of ...

    as this is clearer than drawing parallelograms all over the graph paper. (v) Gradient of line between 1 and 2 minutes for 25% Celery Extract concentration = 0.8 cm3 22.5 seconds = 0.035555555 = 0.0360 cm3/sec (3 sig. fig) (vi)

  1. Reaction of Catalase and Hydrogen Peroxide

    Volume Of O2 (ml) 30 5.8 5.6 35 6.0 6.1 40 9 8.9 45 5.4 5.7 50 4.8 4.3 I have carried out a control experiment with 15% hydrogen peroxide and boiled water. This I did to prove that it was the enzyme catalase that breaks down hydrogen peroxide to water and oxygen.

  2. Investigating the break down of Hydrogen Peroxide using catalyst

    This made it possible to calculate the volume of oxygen produced accurately. It was decided that the length of time left for the enzyme to react with the catalyst would also remain at 1minute. The substrate concentration in the tables shows the volume of hydrogen peroxide/the volume of water Results

  1. The effect of Copper Sulphate concentration on Catalase activity on Hydrogen Peroxide.

    To make sure that they are all the same length. Measuring beaker x2 250 ml One is filled with water and acclimatised, the other one is used to measure with the aid of a syringe also, amounts of solutions. The test tube containing all the reactants will be inserted in

  2. An Investigation on the Effect of Enzyme Concentration on rate of hydrogen peroxide breakdown.

    Volume of Distilled water (cm�) 0 0 10 20 2 8 40 4 6 60 6 4 80 8 2 100 10 0 The table above shows the amount of distilled water and celery extract I will use for each concentration. The 0% concentration of celery extract is used as a control to ensure that

  1. This is an experiment to show how different concentration of celery tissue enzyme, catalase ...

    As we increase the different concentration of celery tissue enzyme the rate of reaction will also increase, it's so as there are more enzymes to catalyse the substrate, hydrogen peroxide. More enzymes mean more active sites available for the substrate, which increases the rate of reaction, as the substrates will have more sites to bind to.

  2. Investigate how changing the concentration of hydrogen peroxide (substrate) affects the rate of reaction ...

    They are known as allosteric molecules. They have a different shape to the normal substrate, and when they enter the alternative sight they change the shape of the active sight. This can have 2 effects: 1. It can stimulate the reaction if the active site becomes a better shape for the substrate to bind with.

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