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

Investigation into the effect of enzyme concentration of catalysers of sucrose by sucrase.

Extracts from this document...

Introduction

Investigation into the effect of enzyme concentration of catalysers of sucrose by sucrase Planning Aim: I aim to find out the effect of enzyme concentration on the substrate. I will try to find out how fast the substrate sucrose is broken down using different concentrations of sucrase, to see if there is a link between enzyme concentration and the rate at which the substrate is broken down. An enzyme is made of protein, they are protein molecules which are called a biological catalyst. These molecules speed up chemical reactions and remain unchanged when the reaction is finished. Enzymes have an active site, this is a place where another molecule or molecules can bind to. These molecules are the substrate of the enzyme. The shape of the enzymes active site will allow the substrate to fit onto it. The substrate is held in place by temporary bond that form between the enzyme and the substrate, the bonds form between the R-groups of the enzymes amino acids and the substrate. Only one type of enzyme will work on one type of substrate molecule. This is because the shape of the enzymes active site will only fit the molecule which will fit into its active site. The enzymes catalyse reactions where substrate molecules are split into two or more molecules. In this case Sucrose glucose + Fructose Sucrose is broken down into two molecules by sucrase into glucose and fructose which are reducing sugars. When the reaction is finished, the products leave the active site and the enzyme is unchanged, then it is ready to receive another substrate molecule. Factors that can affect the reaction rate are the temperature, enzyme concentration and pH. ...read more.

Middle

I will then choose to concentrations which I think don't have a very big difference in time, I will then repeat the experiment ten times on these two concentrations, I will do this so that I can do a statistical test on them. The statistical test will tell me if there is a difference between the two concentrations or if they are the same. I chose to do this method because it worked well when I done my preliminary experiment, so I will use it to do my final experiment. To do different concentrations of sucrase I will have to dilute them. * I will dilute the concentration of sucrase by using distilled water. I will use this because it doesn't contain any chemicals. * I will use a 5cm3 syringe to put the correct amount of sucrase into the test tube. * Then I will use a different syringe to put in the right amount of water to get the right dilution. * To get 1% enzyme concentration I will use 5cm3 of sucrase. * To get 0.8% enzyme concentration I will mix 4cm3 of sucrase and 1cm3 of distilled water. * To get 0.6% enzyme concentration I will mix 3cm3 of sucrase and 2cm3 of distilled water. * To get 0.4% enzyme concentration I will mix 2cm3 of sucrase and 3cm3 of distilled water. * To get 0.2% enzyme concentration I will mix 1cm3 of sucrase and 4cm3 of distilled water. Apparatus: Apparatus Why I chose this apparatus Test tubes Because they can be easily heated and moved around Test tube rack Because the test tubes wont fall over and I will need to set up a lot of test tubes Stop watches Because the are very reliable and accurate, it would give accurate timing Syringe (5cm3 , 1cm3 ) ...read more.

Conclusion

The variation in temperature could have caused an anomalous result. The variations in the amount of benedict's solution used could have cause reaction to take longer to end. I think the reliability of the evidence is good. Every different concentration was put under the same conditions and each solution was measured in the same way. The main source of error was the way that I measured the end point. I used a sample to measure the end point, and I judged the colours with my eyes. The colours could have been slightly different but I couldn't tell. By judging the end point this way, I might have stopped each reaction in different places, meaning each reaction had different end points, this would make my results not very reliable. The sample would also still be reacting, so it would get darker, so near the end of the experiment I would be stopping the reactions at a longer point. I could improved the way I judged the end point by using a colorimeter. I would tell me the exact colour of the solution, so I could stop each reaction at the same place, this would make my experiment much more accurate and reliable. The strong correlation from the data sown in the graphs and in the tables shows that the limitations that have been described has not had a great effect on my result, and my conclusion therefore have a high level of validity. I drew a graph with error bars, which shows that there is no overlap with different concentrations of sucrase. This shows that as the concentration of sucrase increases the reaction time is faster. 1. Jones, M. (ed).(2000).Biology 1. University press: Cambridge. ISBN: 0 521 78719 X 2. Introduction to Enzymes. (2003). Worthington biochem. URL: http://www.worthington-biochem.com/IntroBiochem/effectspH.html 3. Green, N.P., Taylor, D.J. Biological Science, Cambridge University Press, 1984. James Clothier 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. Affect of sucrose concentration on the rate of respiration.

    Eventually, increasing the substrate concentration yet further will have no effect. The active sites will be saturated so no more enzyme-substrate complexes can be formed. This is due to the enzyme concentration being the limiting factor as there are not enough active sites for the substrate molecules to bind with.

  2. To find out how different concentrations of sucrose solution affect the incipient plasmolysis of ...

    A hypertonic solution should exist at 0.6M. Furthermore at 0.7M I predict the greatest decrease in length and mass because more solute molecules are present and less water molecules which means the net movement of water molecules will be out the root vegetables and into the hypertonic solution this should

  1. Investigate the effect of sucrase concentration on the rate of hydrolysis of sucrose.

    Since the active site for all molecules of one enzyme will be made up of the same arrangement of amino acids, it has a highly specific shape. Generally, there is only one active site on each enzyme molecule and only one type of substrate molecule will fit into it.

  2. Catalyse Investigation

    of bubbles Average No. of bubbles 3 3.5 4.5 5.5 6.5 Conclusion In conclusion, I have found that my prediction was correct. The higher the enzyme concentration was, the more oxygen was produced, or in the case of my experiment, more bubbles were produced.

  1. Amylase Investigation

    Remove contaminated clothing. Drench skin with plenty of water. * If split on floor/bench - Wipe off any spillage. Add Sodium thiosulphate solution (20%, 1M) to remaining spill and leave for an hour. Mop up and then rinse with water. During the experiment, heating will be done of substances and therefore burns are a possible hazard.

  2. Investigating the effect of sucrose concentration on the conversion into glucose and fructose by ...

    + (3) Scientific Knowledge Enzymes are proteins that serve as catalysts and accelerate chemical reactions in living organisms. Enzymes accomplish this by lowering the activation energy of the organism it is acting upon, however enzymes will only lower the activation energy of activation for specific organisms, reducing chaotic chemical reactions.

  1. Investigate the factors affecting the rate of breakdown of sucrose by the enzyme sucrase ...

    I believe that the concentration of enzyme is directly proportional to the rate, but this is just a prediction. This could be a factor to investigate. Concentration of Substrate Increasing the concentration of sucrose will affect the rate the opposite way the concentration of sucrase will.

  2. Toinvestigate a factor affecting the rate of  breakdown of sucrose by the enzyme sucrase.

    The pH can affect the enzyme because if it were too low or too high, it wouldn't work at all. The pH disrupts the hydrogen bonds so it needs to perfect for the rate of reaction to be optimal. The concentration of the enzyme and substrate needs to be taken into account.

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