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

To investigate how enzyme concentration can affect the rate of reaction, in this case the breakdown of milk protein by trypsin, a protease enzyme.

Extracts from this document...

Introduction

Biology - Activity 2.10 Enzyme concentrations and enzyme activity Aim To investigate how enzyme concentration can affect the rate of reaction, in this case the breakdown of milk protein by trypsin, a protease enzyme. Hypothesis 1. The higher the concentration of trypsin, the higher the rate of breakdown of milk protein. Reason: with higher concentration of enzyme, there are more active sites available for the substrate molecules to bind with. When there are more enzymes, the collision between enzymes and substrates becomes more frequent, increasing the chance of forming enzyme-substrate complex. 2. Increase in rate of reaction is directly proportional to increase in trypsin concentration. Reason: enzyme concentration exerts a direct effect on the rate of reaction. Apparatus o Milk o Trypsin o 3 Syringes o 5 test tubes o test tube rack o 5 stopwatches o Distilled water Procedure In this experiment, the rate of reaction is determined by the time taken for a given quantity of substrate to be used up: 1. ...read more.

Middle

4. Tap the bases of the test tubes to mix the solutions. 5. Measure the time needed for the milk to turn clear in each test tube. Variables Independent variable Dependant variable Controlled variable Concentration of trypsin Time Temperature Volume of milk Volume of trypsin-water solution Test tube A is a control. Explanation: Test tube A contains distilled water only. It ensures that the clearing of milk in other tubes is due to enzyme activity only and not any other factor. Risk and safety precautions Take care handling glassware. Results Test tube Vol of trypsin/cm3 Vol of distilled water/cm3 Time/s Trypsin concentration/% Reaction rate=1/T A 0 2.0 0 0 B 0.5 1.5 550 25 0.001818182 C 1.0 1.0 364 50 0.002747253 D 1.5 0.5 297 75 0.003367003 E 2.0 0 242 100 0.004132231 Two graphs are plotted. ...read more.

Conclusion

2. Increase in reaction rate is proportional to increase in trypsin concentration. Reason: increase in the number of trypsin molecules results in a proportional increase in the number of enzyme-substrate complexes and therefore a proportional increase in the rate of reaction. Limitations and error 1. This experiment does not measure the initial rates of reaction because the quantity of product formed in a fixed period of time from the breakdown of milk protein is not easily observable. Instead, average rates of reaction are measured by determining the time needed for all milk protein to react, i.e. for the reaction to complete. A graph of average rate of reaction against trypsin concentration does not show an accurate straight line. 2. Tapping and shaking the test tubes too vigorously added kinetic energy to the trypsin and milk proteins, making temperature, the controlled variable, not constant. Improvement Shake the test tubes slowly. ...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 Patterns of Behaviour 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 Patterns of Behaviour essays

  1. Investigation into the digestion of milk by Trypsin.

    in the rate of reaction dropping to nothing as the temperature continues to rise past the enzymes point of denaturisation. I believe that similarly the rate of reaction will be proportional to the pH level until the pH rises past the optimum value of the enzyme.

  2. Investigation On The Enzyme Trypsin

    Average Time taken for reaction Temperature (�C) Reading 1 Reading 2 Reading 3 (Nearest second) 30 365 354 361 360 40 103 105 101 103 50 90 88 89 89 60 80 78 80 79 70 69 70 71 70 Table showing the time taken for the trypsin to digest

  1. Factors Affecting Enzyme Activity

    I think there will be a relationship of proportionality between the concentration of the suspension and the rate of reaction. Below is a predicted graph of results (all measurements are in arbitrary units). I have plotted all five graphs on one set of axes as this will make my results easier to analyse once I have collected them.

  2. THE EFFECT OF BILE SALT ON THE ACTION OF THE ENZYME LIPASE

    Place probe into the beaker of your mixture. 11. Using a burette add drops of sodium carbonate into beaker, until pH reads 10.0pH. 12. You are now ready to record your results: 13. Immediately start recording your graph. 14.

  1. Investigating the effect of enzyme concentration on the hydrolysis of starch with amylase.

    This will cause an increase in rate of reaction. However after the optimum temperature, which is above 40 c, the ionic and hydrogen bonds holding the amylase together will brake and denature, so the reaction will no longer occur. I will keep the temperature constant by keeping it at a mild temperature so the enzymes do not denature.

  2. Effect Of Substrate Concentration On The Activity Of Catalase

    Fair testing: While conducting the experiment, it has to be taken into account that a few variables will have to be controlled so as to ensure that the test is fair. 1. The PH of the reactants should be kept constant.

  1. The effect of concentration on the activity of catalase.

    Repeat the experiment using a different volume of potato. Summary Table As the volume of oxygen produced steadily increased with time for all the concentrations of catalase, I fixed the time at 180 seconds and worked out the rate of reaction for the different concentrations of catalase by the following method.

  2. Investigating the effects of temperature on the rate of clotting milk and Rennet

    Enzymes can be used in both anabolism (the build up of simple chemicals into complex ones) and catabolism (the breakdown of complex chemicals into simpler ones). Enzymes are most commonly used in Catabolism, this particularly applies to animal digestive systems.

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