• 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

An Experiment to find out the Effect of Temperature on the Enzyme Catalase.

Extracts from this document...

Introduction

An Experiment to find out the Effect of Temperature on the Enzyme Catalase Variable How Will it be controlled? Why will it be controlled? Catalase I will measure out carefully 0.3cm3 using a 1cm3 micro pipette It will keep the same volume of enzyme in solution in order for the results to be accurate and valid, because if there is more catalase the reaction will occur faster as more enzyme substrate complexes will be formed. Hydrogen Peroxide I will measure out carefully 5cm3 using a 5cm3 graduated pipette It will keep the same volume of the substrate in solution in order for the results to be accurate and valid, because if there is more Hydrogen Peroxide more oxygen will be emitted and an enzyme substrate complex will be formed more often. pH Buffer I will measure out carefully 0.5cm3 using a 1cm3 micro pipette It will keep the pH levels constant in the solution so that the results are accurate and valid, because if there are more hydrogen ions or hydroxide ions it may affect the rate at which the catalase functions. Light Intensity I will keep the Hydrogen Peroxide in a brown jar It will keep it from breaking down on its own, as if it did the results I obtain would be false and inaccurate. Temperature I will measure it using a Thermometer So that the effect of different temperatures can be investigated Apparatus * Hydrogen Peroxide-This is the substrate of catalase * pH buffers 6,7,8-So that the pH levels can be kept constant * Clamp Stands-To hold the boiling tubes and the gas burette * Gas Burette-It is an accurate way to measure oxygen * Tub of water-To prevent the gas burette from emptying * Boiling Tubes-To carry out the reaction in * Delivery Tube-To transport the oxygen from the reaction to the gas burette * Safety Goggles-To protect my eyes from the Hydrogen Peroxide * Glowing Splint-To test for oxygen in the gas burette * Graduated Pipette-To measure out ...read more.

Middle

I controlled the pH by adding 0.5cm3 pH 8 buffer to every reaction so that hydrogen ions or hydroxide ions were kept constant because they may affect the rate at which the catalase functions. I controlled the volume of catalase each time because if there is more catalase in a specific reaction than in the other reactions it will occur faster as more enzyme substrate complexes will be formed. I controlled the volume of the Hydrogen Peroxide each time because if there is more Hydrogen Peroxide in a particular experiment more oxygen will be emitted, because enzyme substrate complexes will be formed more often. I controlled the light intensity by keeping the Hydrogen peroxide in a brown jar and conducting the entire experiment in the same room. If the light intensity was varied it may have forced the Hydrogen Peroxide to break down faster. Results Preliminary experiment results to work out optimum pH around neutral conditions, at room temperature: ph 6 Time in seconds 1st attempt Oxygen released (cm3) 2nd attempt Oxygen released (cm3) 3rd attempt Oxygen released (cm3) Average Value (cm3) 5 4 0.5 1 1.8 10 10.5 9 14.5 11.3 15 13 11 16 13.3 20 16 12.5 20 16.16 25 19 15 27 20.3 30 25 17 32 24.6 35 34 21 38 31 40 40 27 45 37.3 ph7 Time in seconds 1st attempt Oxygen released (cm3) 2nd attempt Oxygen released (cm3) 3rd attempt Oxygen released (cm3) Average Value (cm3) 5 1.5 3 7.5 4 10 10 13 15 12.6 15 12 16 18 15.5 20 15 19 23 19 25 20.5 24.5 29.5 24.83 30 27 30 39 32 35 35 36 47 39.3 40 41 43 50 44.6 ph8 Time in seconds 1st attempt Oxygen released (cm3) 2nd attempt Oxygen released (cm3) 3rd attempt Oxygen released (cm3) Average Value (cm3) 5 9 12.5 6 9.16 10 19 18 15 17.3 15 25 21 21 22.3 20 29 26 23.5 26.16 25 37 32 28 32.3 30 42 38 ...read more.

Conclusion

This had an affect on the earlier points on my graphs, but not on the general pattern and hence would not have affected any conclusions that I have drawn. If I did this experiment in the future I might unhook the delivery tube each time I wanted to measure a reading from the gas burette. This would help as I would have more accurate readings by creating more time to collect the measurements. I would also use a more accurate syringe to measure out the Hydrogen Peroxide so that the same amount of substrate was added to each reaction, thus giving me more reliable results. It would also help to support the conclusions that I have drawn from this experiment. The evidence I collected is what I expected to find, however in my opinion it is not enough to produce a firm valid conclusion. The maximum yield of oxygen at 35�C is roughly normal although I do expect to find that the optimum would be a little higher, than the max yield that I obtained. In order to produce a firm valid conclusion I would have to repeat the experiment on the temperatures between 35�C-45�C, so that I could find out the exact optimum temperature. Also I would have to conduct the experiment at lower temperatures, on the rising curve, so that I can obtain a full reaction rate curve. I could have also measured the pH in every reaction instead of just relying on the pH buffer to do its job. This would have further validated the results I obtained. ?? ?? ?? ?? This document was downloaded from Coursework.Info - The UK's Coursework Database - http://www.coursework.info/ This document was downloaded from Coursework.Info - The UK's Coursework Database - http://www.coursework.info/ This document was downloaded from Coursework.Info - The UK's Coursework Database - http://www.coursework.info/ This document was downloaded from Coursework.Info - The UK's Coursework Database - http://www.coursework.info/ ...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

    The Effect of pH on Catalase

    4 star(s)

    hydrogen peroxide solution pH buffer solutions (pH 4.5, 5.5, 6.5, 7.0, 7.5, 8.5) distilled water Variables: There are 4 main factors, which affect the activity of enzymes that need to be controlled. 1. Temperature: The reaction is to take place at the optimum temperature of catalase, in a 40oC water bath.

  2. Marked by a teacher

    The aim of this investigation is to find out what effect pH has on ...

    4 star(s)

    in a measuring cylinder making sure you read from the lower meniscus * Measure 10cm� of pH 4.4 solution in a measuring cylinder making sure you read it from the lower meniscus * Put the pH 4.4 solution and H2O2 in the conical flask * Attach the syringe to one

  1. The aim of this experiment is to demonstrate that the substrate Hydrogen Peroxide will ...

    I then washed off the potato cylinder with distilled water. 6. POTATO/HYDROGEN PEROXIDE SAMPLE: I then placed this sample immediately into the sidearm boiling tube. Utilising the pipette filler, I then measured out 10 cm3 of Hydrogen Peroxide. I took Care to view the pipette from the side, to ensure

  2. Investigating the effect of enzyme catalase concentration on hydrogen peroxide.

    When, the apparatus was fully set up and active, the stopwatch was started. Also, the temperature and pH were measured and kept constant before each reading was taken. The timing measured how long the first bubble took to appear and then how many followed the first over the next two minutes.

  1. Investigating the Effect of Substrate Concentration on Catalase

    The smallest change in pH causes the shape of the active site to change, which is made of polypeptides with hydrogen and ionic bonds holding the structure together. This gradually decreases the effectiveness and eventually the enzyme becomes denatured as the active site breaks down.

  2. The effect of hydrogen peroxide on catalase if you change the temperature.

    Place on mashed cylinder into a boiling tube add the measured hydrogen peroxide and attach the rubber bung connected to the measuring syringe. 9. Start stop watch and record volume of gas collected every 30 seconds. At the same time measure the amount of froth produced at 30 seconds intervals

  1. The Nervous System

    Reflex Arc In a simple reflex arc, such as the knee jerk, a stimulus is detected by a receptor cell, which synapses with a sensory neurone. The sensory neurone carries the impulse from site of the stimulus to the central nervous system (the brain or spinal cord), where it synapses with an interneurone.

  2. For my coursework I had to study enzymes (catalysts) and the rate of reaction ...

    Potato borer - To extract suitable sizes of the potato for the test ? Safety goggles - To guard my eyes from the harmful substances. ? Latex gloves - To protect my hands from the irritant substances. All of the apparatus was vital for this experiment as each piece of

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