Lactase Action on Milk Sugars
The reaction of the enzyme, untreated lactase, and whole milk and the reaction of the untreated lactase and skim milk prove to have actually had the enzyme break down its substance. For the enzyme and sucrose reaction, the solution did not have a change in its acidity levels therefore showing that the enzymes did not break down the sucrose. It can be concluded that molecules are quite particular about the molecules they interact and react with. The reasoning behind that is that lactase only breaks down lactose, which is found in milk, while lactase does not break down sucrose.
All the reactions of the heated enzyme with water, skim and whole milk and the sucrose solution all did not result in a change of acidity levels. Because the regular untreated enzyme caused a change in the milk, both skim and whole, reactions both caused a change in acidity levels while the treated enzyme, it is easy to see that the heated enzyme altered the enzyme. When heated to a certain temperature, enzymes can change shape and lose their abilities to speed up chemical reactions. Using that information, the results of treated enzymes and all the solutions didn’t change because the enzyme applied to it already lost its function.
The positive control in an experiment is the group in an experiment where the result is expected. The reactions that were positive controls were reaction A, unheated, and the reaction B, unheated.
The negative control of an experiment is the group in an experiment where the result is unexpected. The reactions that were negative controls of were options D, unheated, D, heated, and E.
Another variable that might also affect the ability of lactase to decompose lactose is pH. In Enzymes.1, the varying amounts of pH on a certain enzyme caused it to lose shape and function. An experiment to test how pH can affect enzymes’ abilities would be to place the same enzyme into different solutions of varying pH’s (10 solutions of pH’s one through ten). Then take the enzymes out and place it into a milk solution. After a certain amount of time, the enzymes will be tested to see how their structure after the time period is compared to the structure before the experiment was conducted. It will also be tested to see how the rate of reaction is different from the rate before the experiment started. I hypothesize that the enzyme will have no change in rate or shape from pH 4-7. The experimental variable will affect lactase activity because the pH levels has the same effect as temperature change on enzymes therefore causing the enzyme to denature at certain pH levels. I think that the optimal environmental condition would be at average body temperature, which is 37 ?C because our bodies use enzymes at that temperature so using that would be ideal.