This lab experiment tested how the enzyme lactase breaks down lactose. Lactase was mixed with milk containing lactose in one test tube, breaking it down into glucose. The same result occurred when lactase was mixed with calcium carbonate and milk. A glucose test strip turned green, indicating the presence of glucose. Sucrose mixed with lactase did not break down, as sucrose does not match the active site of lactase. The results supported the hypothesis that lactase would break down lactose but not sucrose. The purpose was to observe enzyme function and determine that enzymes break bonds in reactants matching their active sites.
13. Calcium carbonateData: See attached graph Table 1: Temperature and Enzymatic Activity Test TubeAMilk & enzymeBMilk & waterCMilk & denatured enzymeDSucrose & enzymeESucrose & water+/- For Glucose +----ObservationsTest strip turns lime-green, slightly aqua+10000s – change30s- same1m30s- sameNo change in test strip color0s – N/A30s- N/A1m30s- N/ANo change in test strip color0s – N/A30s- N/A1m30s- N/ANo change in test strip color0s – N/A30s- N/A1m30s- N/ANo change in test strip color0s – N/A30s- N/A1m30s- N/A Table 2: pH and Enzymatic activity Test TubeA2Hydrochloric acid, milk and enzymeB2Milk and active enzymeC2Calcium carbonate, milk, active enzymeResults: 0 secondsNegativeTest strip: AquaNegativeTest strip: AquaPositiveTest strip: light brownResults: 30 secondsNo changeNo changeNo changeResults: 1 minute 30 secondsNo changeNo changeDevelops foam at top of test tube+1000 Conclusion: The purpose of this lab was to observe how enzymes function and determine their purpose. The major finding was shown in test tubes A and C2.When the enzyme solution was mixed with the milk in test tube A, the enzyme took the reactant (lactose) into the active site and broke bonds to change it from a disaccharide to a monosaccharide. The same goes for test tube C2, when the calcium carbonate was mixed with the enzyme solution, it tested positive for glucose just as test tube A did. They both also changed the glucose test strip’ color when it was emerged in the substance. None of the other test tubes tested positive for glucose. This could have resulted because some of the enzymes were denatured and therefore could not function properly, but also because lactose and sucrose cannot be broken down into glucose and therefore did not test positively. The hypothesis we predicted was mostly supported by the results that the experiment yielded. By predicting that the enzyme solution would be able to break down lactose because the reactant would match with the active site of the coinciding enzyme we were suggesting that all test tubes except for D and E would be able to be broken down since milk contains lactose. D and E were not positive because the lactose enzyme could not break them down. However, only two of the remaining test tubes also were positive for glucose. Those two test tubes contained Calcium carbonate, milk, and active enzyme and milk and the enzyme solution. This shows that the active enzyme we used in the experiment easily broke down the substances shown, which accordingly contained glucose. Test tube A showed a low amount while tube C2 had a very high amount of glucose. There were no errors in this experiment that effected out results so severely to change them. The results that are shown are exactly what were expected to happen, so even if there were some miniscule errors it does not matter. To promote the results of this experiment, it would be best to repeat the process with each test tube and perhaps some other substances as well. By doing so we would be able to tell if our results would remain consistent and if they are truly supported by the hypothesis. The ending result was correct and accepted by the research we had done. In other words, the experiment and data coincide properly with the research and hypothesis, all that happened was expected. Overall, this lab showed the function of enzymes and their effects on other substances such as lactose.
![Katherine Brewer 5 November 2009 Honors Biology Mrs. Donald Enzyme Lab Problem: How does an enzyme break down a specific substrate? Research: An enzyme is an organism inside the body that’s motive is to break and make bonds molecules and speed up chemical reactions by lowering the activation energy needed for them to perform. They are proteins, usually either in tertiary or quaternary structures, and are specific to what they will catalyze (break down or react with). An enzyme’s name usually ends in ‘ase’, for instance lactase, sucrase, and maltase are enzymes. The active site of an enzyme bonds with a reactant and breaks it up into a product that is simpler and the body can digest it more easily. If an enzyme is too severely affected by a highly acidic or basic pH or severe temperatures it can become denatured, and the active site will not react with the substrate in the correct way. Hypothesis: If the ability to react with an enzyme to break down a specific substrate is related to the enzyme lactase then lactase will be able to break down lactose because of the shape of the molecule, but the sucrose will not be broken down because it does not fit with the activation site of the enzyme. Materials: ,[object Object]](https://image.slidesharecdn.com/emzymesareeffinbeast-091206134645-phpapp01/85/Emzymes-Are-Effin-Beast-1-320.jpg)
