• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month
Page
  1. 1
    1
  2. 2
    2
  3. 3
    3
  4. 4
    4
  5. 5
    5
  6. 6
    6
  7. 7
    7
  8. 8
    8
  9. 9
    9
  10. 10
    10
  11. 11
    11

The effect of temperature on an enzyme controlled reaction

Extracts from this document...

Introduction

The effect of temperature on an enzyme controlled reaction Introduction For this investigation I have been asked to investigate the effect of temperature on the rate of decomposition of the substrate hydrogen peroxide when catalysed by the enzyme catalase. The substrate hydrogen peroxide is a naturally produced substance, it is generated as a toxic by-product from the liver and by cell metabolism. Hydrogen peroxide, H2O2, is also produced by white blood cells as a means of killing bacteria. If the HzO2 is not broken down and left to accumulate it can be very serious as it will intoxicate the cells. This is why an enzyme is needed to catalyse the reaction, otherwise hydrogen peroxide would decompose far too slowly, the enzyme being catalase. All biochemical reactions need enzymes to catalyse the reaction, examples of enzyme-aided reactions include all digestion and growth. If there is any chemical reaction in any living thing there is an enzyme helping. Enzymes are made up of a complex of amino acids. The way the enzyme catalyses the reaction is by reducing the amount of energy needed, in essence it provides an alternate path of energy for the reaction, hence it merely speeds up the reaction. ...read more.

Middle

Preliminary work During my preliminary work I used the same method that is described further below. At first I found that using 5 cm3 of yeast and 5 cm3 of hydrogen peroxide was far too much as it kept on overflowing and that 0.5 cm3 of each is very sufficient. I found out that you must ensure the bung is properly secured onto the test-tube otherwise the oxygen is released out. I learnt to be more cautious when setting up the apparatus and making sure that there were no air bubbles trapped in the syringes, for accurate measurements. Once I found the correct measurements I should use I did the experiment and found some results at 100C, which I have included in my table of results further down Apparatus 500ml beaker Some plasticine 10ml calibrated syringe 2x1ml syringe Stopwatch 6xTest tubes 2xsmall beaker Test tube rack Delivery tube Water bath at 10?C, 20?C, 30?C, 40?C, 50?C, 60?C Diagram Method 1. Set up the apparatus as above. 2. Fill 10ml syringe with water and submerge in the beaker, ensuring no air bubbles are present as this could affect your results. 3. Make sure the yeast and hydrogen peroxide are heated up to the temperature being investigated, e.g. ...read more.

Conclusion

I think the reason there were a few slight anomalies was maybe because of slight misreadings or small impurities in the equipment used. Another reason could be that a small amount of oxygen escaped before the bung was put on, or even that if the bung was pushed on very hard a small surge of oxygen could have been pushed into the measuring syringe. Looking at the tables of results some readings for the same temperature seem to have large differences between them. This could be because not all the yeast was properly poured into the hydrogen peroxide test-tube. A major fact that could have affected my results might have been that even though hydrogen peroxide decomposes very slowly, there is still some gradual break down, especially when left in the light in a clear beaker - which is what happened. Overall I personally think the experiment went well, my hypothesis was right, the method worked, and especially considering that it was all performed under school lab conditions. If I had the opportunity to do the experiment again I would try to use more restricted lab conditions. I would try to measure the volume electronically with an electronic counter. Possibly do the experiment in a thermostatically controlled environment. ?? ?? ?? ?? Sean Verrall 28/04/07 1 ...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

    The Effect Of Temperature on the Respiration Of Yeast.

    5 star(s)

    then rate of reaction would be faster and if another batch was not very active then my rate of reaction will be slow giving me inaccurate results. I will control this by trying to complete my experiment in one lesson so I can use the same yeast each time).

  2. Marked by a teacher

    Following the Progress of an Enzyme Controlled Reaction

    4 star(s)

    Other conditions that effect the rate at which a reaction is complete by the influence of an enzyme is the concentration of the enzyme and pH. Outline Method Prepare one boiling tube with the reacting substrate and enzyme in (starch and Amylase).

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

    Manually controlled water bath There was a small number of water baths available, so our experiment couldn't be carried out in the water bath itself, rather I acclimatised the solutions, and the beaker containing water in which the reacting test tube was submerged, for a length of time of 3 minutes.

  2. To investigate the rate at which hydrogen peroxide is broken down by the enzyme ...

    Therefore, it is imperative that safety glasses or, preferably, goggles should always be worn when handling concentrated hydrogen peroxide. If, however, any hydrogen peroxide does get in the eyes, they must be flushed thoroughly with water. Due to this I shall be sure to always be wearing goggles within the

  1. Trypsin. Hypothesis: - I hypothesize that as the temperature increases the rate of enzyme ...

    Mechanism Of Enzyme Action Enzymes are taught to operate on a lock and key mechanism. In the same way that a key fits a lock very precisely, so the substrate fits accurately into the active site of the enzyme molecule.

  2. Investigating the effect of the Temperature on the Enzyme Catalase when it reacts with ...

    * The filter paper is then held over the catalase solution for a short while, so that any extra catalase solution is dropped off. * The Filter paper that was soaked into the catalase solution is then put into the Hydrogen peroxide solution at a angle that is best suitable e.g.

  1. An Investigation to determine the effect of Substrate Concentration on the Enzyme Catalase

    The H2O2 was then injected into the flask. 6) Then immediately the stopclock was started, and the volume of Oxygen collected in the inverted measuring cylinder was recorded every 30 seconds for 5 minutes. 7) Since substrate concentration is the factor, which is being investigated, the experiment was repeated

  2. Daphnia write up

    This further suggests that certain sources of error resulted in parts of the experiment being inaccurate. Nevertheless, all necessary precautions and guidelines were followed to ensure the test was as fair as possible. On the whole, I believe the experiment did work as the results were mainly what were expected.

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