How does temperature affect the rate of reaction for Lipase? As the temperature increases, so will the rate of enzyme reaction. However, as the temperature exceeds the optimum the rate of reaction will decrease. I predict that at temperatures above 70°C the enzyme lipase will become denatured and at temperatures below 10°C the enzyme will become inactive. Since lipase operates within the human body I’d also predict that its optimum temperature would be around human body temperature which is approximately 37°C. I predict that before the optimum temperature the rates will gradually increase and preceding the optimum there will be a drastic decrease in rate until the enzyme is denatured. I predict that the rate of enzyme activity at 45°C will be half that of 30°C. I predict that the rate of enzyme activity at 45°C will be half that of 30°C.
Diagram courtesy of: http://www.rsc.org/Education/Teachers/Resources/cfb/enzymes.htm Diagram courtesy of: http://www.rsc.org/Education/Teachers/Resources/cfb/enzymes.htm
In my controlled assessment I will be investigating the activity of lipase on milk fat at various temperatures so that I can then find an accurate temperature as to when the enzyme works at its optimum; when it becomes inactive and when it denatures. To find when the enzyme denatures is to find out when the bonds of this protein disintegrate and henceforth disable the enzyme from being of any further use. When these bonds break, the protein starts to unfold and loses some its properties. For example, a denatured protein usually becomes less soluble. As an enzyme, it will lose its ability to function as a catalyst. If the stress that is causing the denaturation continues, other changes may occur. Now that the normal structure of the protein is gone, new bonds may be formed, giving it a different shape. The bonds broken in a denatured enzyme is that of which links the polymers to form the amino acids. This means that if lipase were to denature at the higher temperatures it will then cause inactivity in breaking down the fat of the milk hence leaving the unchanged. In this investigation, however, there are numerous factors as to what can affect the investigations results. First of all, the temperature of the room can play a role in altering the results as it can change the temperature of both the solution and lipase. Moreover if one were to move the solution or lipase to another part of the room, or to carry out the investigation on a different day, the temperature surrounding the solution and lipase will change and henceforth change the temperature of the solution and lipase. Secondly, if the temperature of the water bath isn’t precisely the temperature it is supposed to be then, as expected, would change. Thirdly, the age of the contents can affect the concentration of the substrates which would then decrease the rate of reaction with lipase. Finally, there is the factor of human error, as we may not be capable of making perfect measurements consistently the amounts of each component will inevitably change, which would in effect change the results. Of this investigation our independent variable will be the rate of reaction, which we will measure by timing how long it would take for the solution to turn white after having the lipase poured in. Our dependent variable will be the time it takes for the solution to turn pink after having the lipase poured in. Our controlled variable is that of will be all other factors.
Diagram courtesy of http://students.cis.uab.edu/clight/finalprojectwhatisanenzyme.html Diagram courtesy of http://students.cis.uab.edu/clight/finalprojectwhatisanenzyme.html An enzyme is a molecule that changes the speed of reactions. Enzymes can build up or break down other molecules. The molecules they react with are called substrates; enzymes are catalysts. An enzyme works by allowing a substrate, or multiple substrates, to enter the active site, which is where the reaction takes place, and...
Please join StudyMode to read the full document