• 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
  12. 12
    12
  13. 13
    13
  14. 14
    14
  15. 15
    15
  16. 16
    16
  17. 17
    17
  18. 18
    18
  19. 19
    19
  20. 20
    20
  21. 21
    21
  22. 22
    22
  23. 23
    23
  24. 24
    24
  25. 25
    25
  26. 26
    26
  27. 27
    27
  28. 28
    28

This is an experiment to show how different concentration of celery tissue enzyme, catalase breakdown the bonds of hydrogen peroxide, substrate, to produce oxygen given out at different rate of reactions.

Extracts from this document...

Introduction

Aim: - This is an experiment to show how different concentration of celery tissue enzyme, catalase breakdown the bonds of hydrogen peroxide, substrate, to produce oxygen given out at different rate of reactions. Planning Background research:- Catalyst: Catalyst is a substance that speeds up the chemical reactions, without it self being consumed by the process. Any such process is called catalysis. In industries, catalysts are used to speed up many chemical reactions that otherwise will take place too slowly to be practical. Enzymes: Enzymes are proteins. Like other proteins, enzymes consist of long chains of amino acids held together by peptide bonds. Enzymes take part in the breakdown of food materials into simpler compounds. They are also called biological catalyst. This means that by their mere presence, and without being consumed in the process, enzymes can speed up chemical processes that would otherwise run very slowly, if at all. Enzymes are normally named after the reactions they catalyse because their molecular structure is very complex and in many cases unknown. For example, super oxide dismutase is the enzyme responsible for the destruction of the super oxide ion in living organisms. Enzymes are specific. Contrary to inorganic catalysts such as acids, bases, metals and metal oxides, enzymes are very specific. In other words, each enzyme can break down or synthesize one particular compound. In some cases, they limit their action to specific bonds in the compounds with which they react. Most proteases, for instance, can break down several types of protein, but in each protein molecule only certain bonds will be cleaved depending on which enzyme is used. Enzyme Mechanism: One of the unique things about enzymes is that they have one function and one function only. This is to reduce the activation energy. Every substrate in an organism has its own unique enzyme. The substrate, which is to be transformed, fits the enzyme like a key in a lock. ...read more.

Middle

It will produce bias results between the concentrations. Apparatus I will be using the same apparatus for each experiment. If I have the same apparatus the experiment will be same. Further more, it will rule out any chance of it being an unfair test. The one variable that will change Enzyme concentration: Enzyme concentration greatly affects the rate of reaction and is the only variable I will be changing in my experiment. It's so because I want to measure the rate of reaction i.e. the oxygen produced in different enzyme concentrations. To change the enzyme concentration I will dilute it with distilled water. This will give different concentrations of enzyme. This is the way we make different concentrations of enzymes. 10cm3 = 100% concentration 8cm3 + 2cm3 = 80% concentration 6cm3 + 4cm3 = 60% concentration 4cm3 + 6cm3 = 40% concentration 2cm3 + 8cm3 = 20% concentration My hypothesis for this is the more the concentration of enzyme, the more rate of reaction, as with more enzymes we will also have more active sites available to catalyse the substrate, hydrogen peroxide. As we lower the enzyme concentration the rate of reaction will also decrease, as there are only a restricted amount of active sites. . So, although there will be collision occurring between enzyme catalyse, and substrate hydrogen peroxide but very low reaction will occur as enzyme molecule is already occupied by another hydrogen peroxide, as a result of this the rate of reaction will be lower and the amount of oxygen produced will be less. Implementing Results The results of experiment 1 and 2 are given below and so are the concentrations. Experiment 1 100% Oxygen collected (cm3) Time(s) 1 2 3 Average 0 0 0 0 0.0 10 16 17 22 18.30 20 24 30 29 27.6 30 32 37 43 37.3 40 43 45 47 45.0 50 50 48 55 51.0 60 52 57 63 57.3 70 59 63 67 63.0 80 62 66 66 64.6 90 65 64 74 ...read more.

Conclusion

This is because the values for each experiment over the amount of oxygen were not so spread out. Also as the experiment was repeated twice it cut down quite a lot of anomalous results. I also calculated average; it should have improved the accuracy. The results I got were also fairly accurate. This is because they were as I was expecting them to be. All the repetitions were closed to each other and this strengthened my overall end results. This gave me the line of best fit in my graphs. Precision is a component of accuracy, but it is not the same as accuracy. It can be seen in the equipments I used. This can again be seen in the concentration of enzyme concentration as I have explained above. I have listed my limitations and errors and how I could overcome them. My conclusion does agree with my hypothesis in that, the amount oxygen as well as the initial rate of reaction increases, as the rate of reaction gets higher. On the whole my experiment is a well-grounded success, in spite of all the errors and restrictions. References Collins Advanced Science _ Kathryn Senior and Mike Boyle Comprehensive Biology _ Lam Peny Kwan Biology 1 _ Mary Jones, Richard Fosbery and Dennis Taylor New Understanding Biology _ Glenn and Susan Toole Class Notes Advanced Biology _ Michael Kent www.google.co.uk Content page 1. Front Page 2. Content Page 3. Aim and background knowledge 4. Background knowledge 5. Background knowledge 6. Background Knowledge 7. Background knowledge 8. Background knowledge, prediction 9. Prediction 10. Apparatus 11. Apparatus 12. Diagram 13. Methodology 14. Risk assessment and the variables I will control 15. The variables I will control and the variable I will be changing 16. Result 17. Result 18. Result 19. Result 20. Result 21. Graph figure 1 22. Graph figure 2 23. Analysis of results 24. Analysis of results 25. Graph Figure 3 26. Graph Figure 4 27. Analysis of graph 28. Graph figure 5 29. Graph Figure 6 30. Analysis of graph 31. Ratings 32. Ratings 33. ...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

    Beetroot Practical Write up

    3 star(s)

    it be considered a fair test as a larger amount of ethanol may have a larger affect on the cell membrane possible at a faster rate than it would be with a smaller amount. 2. Constant and compromised timing: If the beetroot was left at a longer length of the

  2. Marked by a teacher

    Enzymes - investigate how the substrate concentration (H2O2) affects the activity of catalase on ...

    3 star(s)

    Use plastecine to make sure that the bung with the delivery tube is airtight. * Put six boiling tubes in each boiling tube rack. * Using the glassware marker label the range of hydrogen peroxide concentrations on the boiling tubes.

  1. The effect of enzyme concentrations on the reaction time of Urease active meal.

    Acid - base indicator are organic substances that are weak acids themselves. When a reaction is complete, an indicator changes colour to determine the end-point of the titration. Generally, this can be represented by the following equation: HIn(aq) H+(aq) + In-(aq)

  2. An Investigation Into the Effect of Substrate Concentration On the Rate of Enzyme Activity.

    Another safety risk is the heat block which can get quite hot. If skin came into contact with the heat block then a burn could result. Care should be taken when placing the test tubes into the heat block. If a burn does occur then the effect area should be

  1. Investigation of the effect of adding different concentrations of NaCl to an enzyme-substrate (amylase-starch) ...

    They usually act as carriers, carrying chemical groups of atoms from one active site of one particular enzyme to the active site of another enzyme. Coenzymes that are tightly bound to enzymes are called prosthetic groups. They carry out the same function as coenzymes and can be thought of as 'built in' coenzymes.

  2. The Effect of Substrate Concentration on the Rate of Reaction with Amylase

    It was assumed that the optimum temperature of the amylase was 37-40 degrees C as it is found in human digestive systems, but in fact the true optimum temperature is near to 60 degrees C. Consideration and prediction: Taking in to consideration all the information researched and shown above, my prediction has close correlation to my original hypothesis.

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

    HoIver, the more the substrate concentration there is, keeping enzyme concentration constant, there comes a point where every enzyme active site is working continuously. Even if more is working at its maximum possible rate, known as Vmax.This can be achieved by using the same equipment (the volume of the measuring cylinder may vary slightly from another).

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

    The factors that affect the rate of reaction (decomposition of hydrogen peroxide) are shown below: * Enzyme concentration - the amount of catalase present in celery extract * Substrate concentration - hydrogen peroxide * Temperature * pH level I have chosen to investigate the concentration of the enzyme Catalase.

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