Effect of Temperature on Enzyme Activity

Transcription

1 Effect of Temperature on Enzyme Activity Introduction (Provides background information to the reader to allow them to understand the experiment.) Question Does the temperature effect the activity of an enzyme (Rennin)? Hypothesis Materials 500mL beakers x 3 Stopwatch x 1 Test tube rack Bunsen burner x 2 10mL Measuring cylinder x 2 Retort stand x 3 Thermometers x 5 300mL carton full cream milk Boss Head x 3 Junket tablet x 1 watchglass Ice (approx 10 cubes) 8 x large test tubes Dropper x 2 100mL beaker x 1 Procedure / Method Part A 1. rinse all equipment with distilled water 2. Prepare 3 x water baths at 2 C, 37 C, 80 C with a retort stand and thermometer as per the diagram below: 3. Prepare rennin solution by dissolving 1 junket tablet in 7mL distilled water in a 100mL beaker. Mix thoroughly

2 4. Label test tubes using labels and permanent marker 5. Prepare test tubes as per the table below, but do not add the rennin until all test tubes have reached the specified experimental temperature: Temperature 2 C (As cold as possible) 25 C (room temperature) 37 C 80 C Location Ice bath Test tube rack Water bath Water bath Experimental (E)/Control (C): label E2 C2 E25 C25 E37 C37 E80 C80 Milk (ml) Rennin (drops) Risk Assessment Material Risk Precaution Rennin 6. When all test tubes have reached the experimental temperature, add 10 drops of rennin to each experimental test tube and briefly mix. 7. Record quantitative observations for time taken for milk to clot and qualitative observations on the level of clotting (slightly clotted chunks can be seen through to completely solid). Observations should be taken each minute by gently tilting the test tubes and noting the results in the table in the results section. 8. Reliability: Repeat this experiment 3 times and average the time results 9. Validity: the controlled variables were kept the same for all experiments. Part B: Denatured or not? 10. At the conclusion of part 1, place the test tubes from the 80 C water bath and the ice bath into the 37 C water bath. Resume observations to determine if restoring the enzyme to the correct temperature restores enzyme activity. Variables Independent variable: (The variable changed by the scientist) Dependent variable: (The variable measured by the scientist) Controlled variables: (All the things that are kept the same for each part of the experiment directly linked to validity)

3 The control (The removal of the independent variable) Results: (This section presents the data collected in the experiment) Part A Time (sec) C (As cold as possible) 25 C (room temperature) 37 C 80 C Part B Time (sec) C Change to 37 C 80 C Change to 37 C

4 Graph: time taken to clot at various temperatures. (Remember: the independent variable = x axis)

5 Discussion: Should include: Did you see what you expected to see? If not, then why not? An analysis of the results what was the trend? What problems did you encounter? What steps could you take to improve the experiment? Would these steps make this experiment more Valid and more Reliable? Did your results reveal anything interesting that could be investigated further in another experiment? Conclusion (A short statement of your findings, usually written in relation to the Hypothesis: Did the results support or refute the Hypothesis)

6 References: 1. Function of Rennin Enzyme. (n.d.). Retrieved October 25, 2017, from 2. The Editors of Encyclopedia Britannica. (2016, April 11). Rennin. Retrieved October 25, 2017, from