Enzyme- Controlled Reactions
- By the end of the day, I will be able to carry out an experiment involving enzymes (a type of protein) where the enzyme may be affected by varying the pH in which the reaction occurs by doing a virtual enzyme-controlled reactions> online and completing a formal lab report in a webpage portfolio.
- I will be sure to control the experiment and change only one variable at a time
A)ProblemThe purpose of this lab is to observe how enzymes act on substrates to produce
products. We will observe how enzyme activity is altered when the enzyme environment's pH is changed. |
C) Materials
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B) Hypothesis
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D)Procedure
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E) ResultsData Table> (hyperlink your data table here; make a copy of mine to start you off as seen here>)Paragraph form: Describe every observation made with each step. Use scientific terms and be specific.
In step 1, I observed 5 test tubes in which I would conduct the experiment in. In step 2, I changed the pH's so I would be able to conduct the experiment with different variation pH's. In step 3, I observe that I add lactase to each of the varying pH's. In step 4, I observed that the color in each different pH tube was changing. In step 5, I observed the amount of molecules that were being formed per minute. In step 6, I just repeated step 4 with different experimental numbers. Data Table: https://docs.google.com/a/sweetwaterschools.net/spreadsheet/ccc?key=0AguKDb1dONdvdDhYdnM5eFE5d3NyaHRMZ3ZWa3NmdGc&usp= drive_web#gid=0 |
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F) Conclusion
Virtual Lab> Journal Questions
Paragraph form conclusion
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Include what you learned, errors, justification for conclusions, explanation of results. Tips on what to include in your conclusion:Re-state hypothesis and results briefly. Explain what was learned by observations and calculations. What deductions can you make? What commonalities are observed, if any? Do NOT include results not mentioned previously. How would you change or improve the lab next time? What experimental errors could not be avoided.
- Describe the relationship between substrate concentration and the initial reaction rate of an enzyme-catalyzed reaction. Is this a linear relationship? What happens to the initial reaction rate as substrate concentration increases? The more pairs of enzymes and substrates that are made, more product will be made.
- What is the maximum initial reaction rate for the lactase enzyme at pH 7? The maximum initial reaction is 350 molecules being formed.
- Explain why the maximum initial reaction rate cannot be reached at low lactose concentrations? The maximum initial reaction cannot be reached at a low lactose concentration because there are some enzymes that are not reacting.
- What does your data indicate about the optimum pH level for this lactase-catalyzed reaction? This indicates that lactase is better with the pH of 7 because that is where the highest enzyme activity is.
- Enzymes function most efficiently at the temperature of a typical cell, which is 37 degrees Celsius. Increases or decreases in temperature can significantly
lower the reaction rate. What does this suggest about the importance of temperature-regulating mechanisms in organisms? Explain. If the active site is destroyed, it would be called denaturing. This effects the proteins, enzyme productivity, and its ability to react. - People with a lactose intolerance are able to take products such as Lactaid that contain the lactase enzyme with their meals. These products can be taken in pill form. Considering the fact that the pill form of the enzyme would have to travel through the person's stomach, what special consideration would the producer of this product need to be concerned about? They should consider having enough lactase to counteract the lactose and making sure that it is at a neutral pH because lactase works best at pH 7.
Paragraph form conclusion
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Include what you learned, errors, justification for conclusions, explanation of results. Tips on what to include in your conclusion:Re-state hypothesis and results briefly. Explain what was learned by observations and calculations. What deductions can you make? What commonalities are observed, if any? Do NOT include results not mentioned previously. How would you change or improve the lab next time? What experimental errors could not be avoided.