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

In this investigation my aim is to find out how the concentration of enzyme (amylase) will affect the rate of reaction.

Extracts from this document...


Scientific Knowledge An enzyme is a biological catalyst and affects every reaction in the body. Without enzymes in the body metabolism would be at a rate too slow to sustain life. Enzymes are used in the body for both anabolic and catabolic reactions for example the enzyme amylase breaks down starch into maltose for absorption into the blood. This investigation will consider the factors (in particular enzyme concentration) that affect the break down of substrate by amylase. The Lock and Key theory states that every enzyme can break down a certain type of substrate. This is because the active site(s) will only fit that particular substrate or group of substrates. This is like a key fitting a lock and the reaction that occurs being like the key turning in the lock. Enzymes work by lowering the activation energy for the reaction; this may be due to the way they hold the substrate molecule(s). In collision theory it states that for a reaction to occur the particles must collide and with sufficient activation energy, an enzyme therefore increase the rate of reaction by facilitating reaction initiation. ...read more.


'Average' was calculated as a mean of values form tests 1-7 for each amylase concentration. 'Rate' was based on the average using the formula Starch Digested / Time Taken To Digest= Rate mg/sec Conclusion In the results we can definitely see that as the concentration of Amylase is increased the rate also increases. This is because as the concentration of Amylase increases the number of active sites for reaction to occur will also increase meaning that more collisions could occur every second therefore allowing the starch to be digested faster. We can also see through the graph that the speed is not exactly doubled as the concentration is doubled this may be because of wasted collisions between the enzyme and the substrate. In a wasted collision the substrate does not join to the enzyme as it does not hi the active site fully this means that the collision does not result in a reaction therefore no starch is digested into maltose. I can see that my prediction was partly correct as I had stated that as the concentration was increased the rate would also increase. But the results did not double as the concentration was doubled as I had stated but this may be down to other factors that we had not accounted for. ...read more.


This equation shows the reaction 2H202 O2+H2O this shows us that the Hydrogen peroxide is broken down into water and oxygen and this oxygen could be used to measure the rate of the reaction. The experiment could be carried out using this method. Method 1. Set up equipment as in diagram. 2. 3. Set timer for 3minutes and place a measured amount of liver in the beaker and start time. 4. After the time has finished remove the delivery tube from the tub leaving just the measuring cylinder and then measure the amount of oxygen produced. Record this in a table. 5. Repeat this for concentration 0.25%, 0.50%, 0.75, 1.00%, 1.25%. 6. Record these results repeat practical under same conditions 3X. 7. Work out averages and rate of reaction and draw graph. This method would produce accurate results as nothing is subjective to a person's opinion and also as the experiment is repeated 3 times under the same conditions the results would be quite accurate. An alteration that could be made is that instead of liver, catalyse could be by itself which would give a more accurate results because the weight could be altered due to density or even water content. ...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. Rates of Reaction - The Iodine Clock

    0.001 0.002 0.003 0.004 0.005 0.006 RESULTS 2 Concentrations for set: Varying volume Hydrogen Peroxide Na2S2O3 0.025M KI 1M H2O2 2 Volume H2SO4 1M TRIALS: Volume (ml) H2O 172 170 164 169 164 159 166 156 Na2S2O3 2 4 10 10 10 10 10 10 KI 10 10 10 5

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

    Prediction I predict that the higher the enzyme concentration, then the higher the rate of catalyse activity; this is because there will be more active molecule for a reaction occur. More active molecules give more chemical reactions since there will be more successful collisions at the active site of the enzyme and substrate.

  1. Enzymes - show how substrate concentration affects the rate of reaction for an enzyme ...

    This is mainly because enzymes have preferable working condition in which they work. So if an enzyme works best at neutral conditions, pH7 and pH is changed to be acidic then the enzymes will denature as hydrogen and ionic bonds break.

  2. Investigation On The Enzyme Trypsin

    between incubation times is 3.8%, that suggests that on average 3.8% of the functional trypsin becomes denatured every minute that it is at 50�C. The reason for the expediential decay is that when at 50�C, trypsin has a certain chance of survival.

  1. Catalase activity in the liver

    DESCRIBE YOUR PROCEDURE APPARATUS 2 Measuring cylinders 4g of liver 2 Measuring beakers 8 Thermometers 49 Test tubes 8 Test tube racks 8 Water baths Ruler Hydrogen peroxide Pestle and mortar Funnel 200ml of water DIAGRAM METHOD (Making the stock solution)

  2. A-Level Investigation - Rates of Reaction – The Iodine Clock

    I am therefore required to perform three different experiments, changing the concentration of a single variable in each one. This will mean that the variables, independent and controlled, will change in each 'set'. All experiments should be performed at standard temperature and pressure (S.T.P.) - 298K and 1 ATM pressure.

  1. The effect of enzyme concentration on the rate of amylase and starch reaction.

    -Volume of Solutions. -Amount of iodine. I will change these variables: -Concentration of amylase (already adjusted into neutral PH) Preliminary work Before I did the method I used a spotting tile technique to see how amylase breaks down starch and here are my results: Starch alone Black Mixture straight

  2. Does the Volume of Amylase Affect the Rate of Reaction between Amylase and Starch?

    It does this by measuring the light absorption of the solutions obtained and comparing them to a standard. To set the standard of the colorimeter, a cuvett with a substance in that has the same properties that is desired at the end of the experiment (In this experiment it will be distilled water), is placed in the colorimeter.

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