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The aim of this activity is to investigate the effect of a reduction in enzyme concentration on the rate of reaction, in this case the breakdown of protein by protease enzymes.

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Introduction The pancreatic duct in individuals who have cystic fibrosis frequently becomes blocked, reducing or preventing the release of pancreatic enzymes into the small intestine. The aim of this activity is to investigate the effect of a reduction in enzyme concentration on the rate of reaction, in this case the breakdown of protein by protease enzymes. Purpose Milk powder contains a white protein called casein. A white suspension of milk powder clears on the addition of the enzyme trypsin. The aim of this experiment is to investigate the effect of enzyme concentration on enzyme activity. We will observe how fast the milk turns transparent by changing the concentration of the enzyme on milk. Hypothesis The higher the concentration of trypsin, the higher the rate of breakdown of milk protein because 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. ...read more.


To avoid random errors, I have to control changes in the material used or the conditions in which they are carried out in, as this will all affect the final result we produce. Method Test Tube 1ml % Trypsin ml of water ml 0.5% Trypsin A 0 1 0 B 0.5 0 1 C 0.375 0.25 0.75 D 0.25 0.5 0.5 E 0.125 0.75 0.25 In this experiment, the rate of reaction is determined by the time taken for a given quantity of substrate to be used up: 1. Prepare trypsin solutions of different concentrations by mixing trypsin and distilled water together. Two syringes are used to measure and transfer different volumes of trypsin and distilled water separately. Label the test tubes: 2. Tap the bases of the test tubes to mix the enzyme-water solutions. 3. Use another syringe to measure 2cm3milk and transfer into each of the 5 test tubes. Start each stopwatch once milk is added into each test tube. ...read more.


The variance of this suggests that there is an error within the results. The reason for this error may be identified as error systematic error and random error. An example of systematic error is if the solution was made up incorrectly. For example too much enzyme may have been added and too little water. Also, at 0 it took a longer time but the solution did not change. Random error can also been the reason for the error within the result. An example of this is tiredness of the determining the end point of the solution. Also, as time was limited many of the recorded results may have been rushed. As a result of this, the accuracy of the results may have been affected. To gain a more reliable result, more repeats should have been done and an overall average should have been worked out. Also other variable such as the concentration of the substrate i.e. the milk is to be kept constant and the temperature is also to be kept constant. ?? ?? ?? ?? Jenita Radhakissoon ENZYME CONCENTRATIONS AND ENZYME ACTIVITY ...read more.

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Here's what a teacher thought of this essay

3 star(s)

A good write up, the theory in the introduction is informative and reinforces the hypothesis. The results table is a little confusing but the conclusion hightlights what may have gone wrong and ways in which to address it next time. Unfortunately there is no graph which would have added to the overall strength of the piece of work. 3 stars.

Marked by teacher Louise Star 10/04/2013

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