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See if the concentration of the substrate (milk) will effect the rate at which the enzyme Lipase can digested fat into fatty acids and glycerol.

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Science Investigation My Task My task is to see if the concentration of the substrate (milk) will effect the rate at which the enzyme Lipase can digested fat into fatty acids and glycerol. These are the different variables for this experiment and what effect they have on the experiment. Concentration of the enzyme - The higher the concentration the more enzymes there are to react with the substrate. The concentration will effect how fast the reaction will happen. If the concentration of the enzyme is high, the reaction of the enzyme will be fast. Concentration of the substrate (milk) - The substrate is what the enzyme reacts with. It will effect how long it takes the enzyme to digest. The higher the concentration of the substrate, the faster the reaction will be. Temperature - The temperature effects the enzyme, not the substrate. The temperature makes the enzyme move. The higher the temperature, the faster the enzymes will move, causing a faster reaction. pH of the solution - The pH of the solution will effect the enzyme. It will not effect how fast the reaction will take place. Enzymes work best in neutral conditions. So, if the solution is too acidic of too alkaline the enzymes will not work. The variable I am going to investigate is the concentration of the substrate. ...read more.


+ 3 ml3 5a 1 ml3 + 4 ml3 5b 1 ml3 + 4 ml3 How will you make it A Fair Test? I will try to make this experiment as fair as possible by keeping everything the same apart from the amount of milk and water I add as the substrate. Some examples of what I will keep the same are: the same source of water, the same equipment used, the same quantities of the different solutions. I will do each test twice to get a more accurate reading. Using a stopwatch for each test will make the timing of the test more accurate. The syringes that will be provided for us in this experiment will enable us to accurately measure our solutions. Apparatus Used for Each Test Done Pipette Stirring Rod Test Tube syringe 10 ml Lipase 3 ml Phenolphthalein Milk 2 ml 5 ml Water Sodium Carbonate Solution The amounts of different substances Depends on what test you are doing (Look at table above). Results Experiment Number Minutes Seconds 1a 7 minutes 10 seconds 1b 5 minutes 27 seconds Average 6 minutes 31 seconds (nearest whole second) 2a 8 minute 45 seconds 2b 6 minute 52 seconds Average 8 minute 08 seconds (nearest whole second) 3a 9 minutes 43 seconds 3b 12 minute 58 seconds Average 11 minutes 02 seconds (nearest whole second) ...read more.


Was the your method of carrying out the experiment done well? Where there any Problems? I think our method of carrying out the experiment was done well, because there were hardly any problems. Our only problem with carrying out the experiment was our own clumsiness. When stirring the solutions, I accidentally made a hole in the bottom of the one of the test tube, we had too stop the experiment and repeat this test, and this was our only problem, which was a minor set back. How Could You Improve the Experiment I could have improved the experiment by using distilled water instead of tap water. Distilled water is pure water, so there are no chemicals in it so there would be no chemicals interfering with the results. Having a certain amount of time I stir the solution with every experiment would make it just that much fairer, but it would still be unfair because I can not measure the speed I stir the solutions. In addition, I could have repeated the test more times to get results that are more accurate. Ideas for Further Experiments * Could test different enzymes with different substrates. * Do not dilute the substrate and change the temperature. * Change the amount of enzyme added. * Do not dilute the substrate and change the pH of the solution. By Steph Jones 10Q ...read more.

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