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

An Investigation on the Effect of Inhibitor Concentration on Reactions involving Acid Phosphatase.

Extracts from this document...

Introduction

An Investigation on the Effect of Inhibitor Concentration on Reactions involving Acid Phosphatase. Katherine Pears CONTENTS Introduction and Hypotheses: Introduction...................................................................Page 3 Pilot Study Summary.......................................................Page 3 Hypotheses...................................................................Page 3 Theory..........................................................................Page 4 Methods: Apparatus List................................................................Page 9 Pilot Study.....................................................................Page 9 Method.......................................................................Page 12 Choice of Techniques....................................................Page 13 Controls......................................................................Page 15 Risk Analysis...............................................................Page 16 Analysis: Data Tables...............................................................Page 17 Graphs........................................................................Page 19 Discussion and Evaluation: Explanation..................................................................Page 22 Error analysis...............................................................Page 22 Limitations...................................................................Page 24 Suggestions for Further Study.......................................Page 24 Appendices Bibliography.................................................................Page 26 An Investigation of Inhibitor Concentration on Reactions involving Acid Phosphatase. INTRODUCTION AND HYPOTHESES Introduction I have decided to investigate the effect of altering the concentration of an inhibitor, on an enzyme catalysed reaction. I will be investigating this with the reaction aided by the enzyme acid phosphatase, in which phenolphthalein and phosphates are released. The inhibitor being used will be sodium dihydrogen phosphate. Pilot studies lead to this idea as they were successful and the most interesting theory was provided using this variable. Pilot Study Summary I carried out a pilot study which involved demonstrating the effect of an inhibitor on the reaction involving the breakdown of phenolphthalein. This developed into an investigation on the effect of inhibitor concentration on an enzyme catalysed reaction. Null Hypothesis There will no effect of changing the amount of inhibitor used. The % transmission will remain constant for all solutions despite varying concentration of inhibitor. Alternative Hypothesis As the concentration of sodium dihydrogen phosphate is increased the rate of reaction will decrease. This will be indicated by a decrease in % transmission as concentration of inhibitor decreases. THEORY The reaction that I am investigating is: In this reaction the enzyme is acid phosphatase. The definition of an enzyme is a globular protein which acts as a biological catalyst, increasing rate of chemical reactions, without itself being permanently changed [7]. The enzyme acid phosphatase assists reactions in which phosphate compounds are broken down releasing phosphates. In this case the compound phenolphthalein diphosphate is used to act as an indicator of the rate of reaction. ...read more.

Middle

I obtained the following results: Results for Pilot 3 Concentration (M) % transmission (blue filter) 0.10 90.00 0.09 88.00 0.08 88.00 0.07 88.00 0.06 88.00 0.05 86.00 0.04 86.00 0.03 86.00 0.02 84.00 0.01 79.00 0.00 39.00 As expected there was not enough variation in my results to carry out a worth while investigation. I then decided to vary the concentration between 0.00M and 0.01M rather than 0.1M. From this pilot study I decided on the range of inhibitor concentration I would be using. Method 1. Place a 250mL glass beaker on a balance and tare, weigh 30g of mung beans into the beaker. 2. Place mung beans and 30mL of water in a pestle and mortar. Add a small amount of sand and grind into a pulp. 3. Place muslin cloth over mouth of 50mL beaker. Use an elastic band to hold cloth in place if necessary. 4. Squeeze pulp through a muslin cloth into a 50mL beaker. Divide the liquid evenly into a 4 centrifuge tubes use a 25mL measuring cylinder to achieve equal volumes. Centrifuge at 60 r.p.m for 5 minutes. 5. Pour supernatant into a clean 50mL beaker and dispose of pellet. 6. Place 11 boiling tubes in a boiling tube rack. 7. Use a 1 cm3 pipette to measure 1 cm3 of 1% phenolphthalein diphosphate solution, add 1 cm3 to each boiling tube. When measuring volumes of liquids measure from bottom of meniscus and check this at eye level. 8. Use two 10 cm3 pipettes to make up different concentrations of buffer pH5 and 0.01M sodium dihydrogen phosphate. Make following concentrations: Concentrations for Experiment Concentration (M) Volume of 0.01M inhibitor (cm3) Volume of buffer 5 (cm3) 0.010 10.00 0.00 0.009 9.00 1.00 0.008 8.00 2.00 0.007 7.00 3.00 0.006 6.00 4.00 0.005 5.00 5.00 0.004 4.00 6.00 0.003 3.00 7.00 0.002 2.00 8.00 0.001 1.00 9.00 0.000 0.00 10.00 9. ...read more.

Conclusion

I had enough space to carry out the experiment well. As I was only slightly limited by time all that may have been sacrificed is attention to detail. If i had had access to professional apparatus such as a spectrophotometer, then the accuracy in my experiment may have improved. Suggestions for Further Study Obviously to gain a further understanding for this topic I would carry out tests at more concentrations of inhibitor. I would especially aim to gain more results for the concentrations of inhibitor between 0.01M and 0.02M. I would do this as this is where the graph levelled off. By obtaining these values I would find where the maximum inhibition. To obtain these concentrations I would make up the following: Inhibitor Concentration (M) Volume of buffer 5 (cm3) Volume of 0.02M Inhibitor (cm3) 0.010 5.0 5.0 0.011 4.5 5.5 0.012 4.0 6.0 0.013 3.5 6.5 0.014 3.0 7.0 0.015 2.5 7.5 0.016 2.0 8.0 0.017 1.5 8.5 0.018 1.0 9.0 0.019 0.5 9.5 0.020 0.0 10.0 To these concentrations I would add the constants to each boiling tube as in the experiment I carried out in this investigation. These were 1cm3 of substrate, 1cm3 of enzyme and 5cm3 of alkali. I would then obtain these results in the same was as in this investigation. Also to further my knowledge on this topic I would carry out the experiment in the same way but change the variable of pH. This would show me what the optimum pH for the enzyme acid phosphatase is. I have researched this but to be sure which is the best I would carry out an experiment to show this. To do this I would not use any inhibitor, as this slows down the reaction and in this case this is unnecessary as inhibitor concentration would not be investigated. I would add the same volume of buffer, enzyme and substrate to each boiling tube. The variable would be the pH of the buffer. To vary this I would add the same volume of different pH buffers to each boiling tube. ...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 Substrate Concentration on Enzyme Action.

    4 star(s)

    A small number of the amino acids make up the enzymes active site. This is the part of the enzyme where a substrate will fit forming an enzyme substrate complex. The products are released from the active site leaving the enzyme free to combine with another substrate.

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

    80 1 2 3 3 3 2 2.5 90 6 7 6 5 6 5 6 100 6 6 5 6 8 6 6 Table 6: 1/T - The effect of Increasing Temperature on activity of Catalase Enzyme and median 1/T (immobilised)

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

    Using the markings on the 50cm� beaker pour 50cm� of NaCl solution into a beaker and label it 'NaCl.' 5. Using the markings on the 50cm� beaker pour 50cm� of distilled water into a beaker and label it 'Water.'

  2. A Level Biology revision notes

    the gut o This causes watery diarrhoea * Other symptoms: vomiting, abdominal pain * Management o High fluid intake o Often self-limiting, don't require treatment o Severe cases, take stool culture and use antibiotics Vibrio Cholera * Produces enterotoxins released from bacteria o Enters enterocytes (cells lining the surface of the intestine)

  1. WHAT EFFECT DOES SUBSTRATE HAVE ON THE RATE OF RESPIRATION IN SACCHAROMYCES CEREVISIAE?

    the boiling tube via the delivery tube attached to it, and then enter the gas syringe at the other end form which readings can be taken. 11. At regular intervals of 5minutes, take readings of the volume of CO2 made from the gas syringe recording each reading on a results table.

  2. Catalyse Investigation

    I would also use a measuring syringe to measure the amount of oxygen because this is a much more accurate way of doing it. For this investigation I have been asked to investigate (by experimentation) the effect of substrate concentrations on the rate of the decomposition of hydrogen peroxide when catalyzed by the enzyme catalase.

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

    Trypsin is an enzyme found in the small intestine and prefers a pH of about 8. The tertiary structure of a protein depends on interactions such as hydrogen bonding, between R groups. A change in pH can alter the ionisation of these side chains and disrupt the normal configuration and in some case denature the enzyme.

  2. Amylase Investigation

    Oxidizing enzymes, known as oxidases, accelerate oxidation reactions; reducing enzymes speed up reduction reactions, in which oxygen is removed. Many other enzymes catalyse other types of reactions. Enzymes work by bonding molecules so that they are held in a particular geometric configuration that allows the reaction to occur.

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