• 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

Investigating the Rate of Reaction In Enzymes

Extracts from this document...

Introduction

INVESTIGATING THE RATE OF REACTION IN ENZYMES Robert Smith Our aim is to investigate the factors that affect the rate of reaction in enzymes, in this case amylase, and its substrate: starch. To investigate this there are three possible variables that should be considered: * Temperature, * pH, * Concentration. I have chosen to do temperature as I feel that I can do this experiment the most effectively and know more about temperature in relation to enzymes than the other two variables. Some enzymes behave/react differently with their substrate at different temperatures. Amylase reacts optimally at quite high temperatures; above 50 degrees Celsius. Below that, as the temperature decreases, the rate of reaction slows. This is because the lower the temperature the slower the molecules move around in the mixture of enzyme and substrate solution. This means that there is less of a chance of a substrate molecule coming into contact with and enzyme molecule than if they were moving faster. So the higher the temperature the faster the molecules move around so the higher the chance of the 'lock and key' or enzyme and substrate coming into contact with each other so the faster the reaction. However, at a certain temperature somewhere above 50 degrees Celsius the enzyme will denature and the substrate will no longer fit into the active centre of the enzyme so the rate of reaction will slow to a stop above a certain temperature. ...read more.

Middle

I have decided that to make this investigation reliable and to have a decent set of results to analyse at the end that I should take five sets of different temperature results. The diagrams below show how I plan to conduct my experiment in relation to the apparatus listed previously. The following table displays the results obtained from the preliminary experiment. To get a better impression of what the results mean I have plotted them on a graph: The graph shows an obvious negative correlation when a line of best fit is drawn. This means that the higher the temperature the faster the reaction took to finish. I decided not to take more than one reading for each temperature because all I needed was a rough idea of whether or not my method worked. From these results you can't tell where or if the enzyme denatures. This is because the temperature range I used didn't go up quite high enough, so in the main experiment I will have a temperature range that includes a higher top temperature to try and discern when the enzyme denatures. I will also take a wider temperature range. Seeing as how this preliminary experiment worked well, looking at the results I obtained, I will use this same method for the main experiment, repeating each experiment reading twice. ...read more.

Conclusion

The pH was controlled because every substance used in the investigation was taken from the same source. The concentration was controlled because each batch of starch and amylase was measured accurately before mixing. I can't think of any way that the rate of reaction may have been affected, other than by varying the temperature, which was intentional. The results were indeed accurate in relation to each other as two repeats of each individual temperature experiment were made to ensure maximum accuracy. The reaction completion times were all quite close together, implying an accurate procedure as the results were not spread all over the shop. The control I conducted clearly showed that the amylase was the only catalyst of the biochemical reaction that turned the starch into maltose. If I had to repeat this investigation I would take an even wider range of temperatures into account to encompass the denaturing point of the enzyme because this is an important part of investigating how temperature affects the behaviour of the enzyme. Because I feel that otherwise the experiment went well and the method was foolproof, I would follow the same procedure and use the same variable and use the same equipment. If I had had more time I would have liked to have looked at more/different variables and looked at different enzymes and their substrates and see how the variables affected their behaviour as well. ...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)

    The only concentration on my graph that has a larger range bar in comparison to the other range bars is the 4% concentration. This is due to the fact that one of the results for this concentration was an anomalous result, and was left out when calculating the average result.

  2. Marked by a teacher

    "To Clone or Not to Clone- That is the Question".

    4 star(s)

    Although at present, human cloning is much too difficult and expensive for it to be taken to a larger scale, but as science progresses, anything may be possible and cloning could become a common practice. Also, rewinding back to the beginning when the situation of Joseph Mengele was mentioned: what if it does become possible to create armies of clones?

  1. Investigating the Rate of Reaction of the Enzyme Amylase on starch

    The rate begins to decrease as more and more enzymes become denatured. The diagram below shows a rough representation of how the structure of the enzyme changes when it is denatured. As you can see the active site, which was once a cleft in the structure has basically disappeared.

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

    So the rate of reaction is directly proportional to the temperature. I will keep the temperatures other than that on which I am working constant. This I will do by keeping the air conditioner off, so that the room doesn't become cold and lowers the temperature of the solution. 6.

  1. Catalyse Investigation

    Temperature - As temperature increases, molecules move faster (kinetic theory). In an enzyme catalysed reaction, such as the digestion of sucrose into glucose and fructose, this increases the rate at which the enzyme and substrate molecules meet and therefore the rate at which the products are formed.

  2. 'Investigating how temperature affects the rate action of the amylase enzyme on starch.'

    (I will be using starch in a liquid form) * Time: Obviously this is a variable that is common to all reactions; this variable must be kept the same in order to sustain a fair test. Safety Precautions: For both Preliminary and Official experiments When I carry out my investigation I will have to take under consideration some safety precautions.

  1. Spreadsheet cwk sandwich shop prices

    I can perform calculations * I can perform formulas to make calculations * I can format cells * I can change the font size and style * I can change the text alignment * I can add borders and lines * I can insert extra rows and columns * I

  2. Factors That Affect the Rate of an Enzyme Reaction.

    This type of reaction where a substrate molecule is broken down into smaller pieces is called an anabolic reaction. Word and balanced symbol equation for the decomposition of hydrogen peroxide: Hydrogen Peroxide + Catalyse ==> Oxygen and Water 2H202 + Catalyse ==> 2H20 + 02 To obtain a good scope

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