Question
Please help with the following questions from an Enzyme Kinetics Lab.
Trials were performed by taking a DP of triiodide and adding it to test tubes then adding a DP (DISPOSABLE PIPETTE) of a solution comprised of the items in the trials. Reaction time and starch concentrations were considered when determining rates. SCROLL DOWN FOR MORE CONTEXT (IN GREEN).
1st and 2nd Trial
1mL of Amylase (.05%)
1mL of Starch (.30 wt%)
3mL of Buffer (4.5-5.5 pH)
All added to 20 mL of Water
3rd Trial
2mL of Amylase
1mL of Starch
2mL of Buffer
All added to 20 mL of Water
4th Trial
1mL of Amylase
2mL of Starch
2mL of Buffer
All added to 20 mL of water
21. DISCUSSION The reaction solution actually tested in this experiment was from the DP, not in the reaction flask. Why didn't you test the reaction solution that was in the flask? The solution in the flask was not reacting. Only the DP had the reacting solution The solution in the flask could not be quickly added to a test tube, so a DP was used The solution in the flask stopped reacting when the DP was connected The DP removed most of the starch from solution in the flask. Which of the following errors do you think is most significant when using the DP to hold the reacting mixture? The DP might not dispense exactly the same volume of solution into each TT The DP might not be maintaining the reaction solutions at a constant temperature, and reaction rates are temperature dependent The DP might not be removing all of the reaction solution The DP might introduce contaminants from previous trials into the reaction solution Which of the following is the best suggestion for how to improve this experimental procedure by minimizing experimental errors? Remove less reaction solution by using a smaller DP Use a new DP to remove some of the reaction solution before each addition to a test tube Heat the reaction flask to 70O C before starting the reaction Keep the test tubes in an ice bath Based upon your conclusions about the reaction kinetics, how long would it take to digest starch in the absence of any amylase enzyme? If the amylase concentration were zero, it would take twice as long as in trial #2 to digest the starch If the amylase concentration were zero, starch digestion would also take nearly zero time (it would be instantaneous) If the amylase concentration were zero, the starch concentration could only be tested when close to zero, too. If the amylase concentration were zero, the digestion of starch would require a much longer time
Explanation / Answer
1) option A. the solution of the flask was not reacting. only DP had the reacting solution.
2) option A. the DP might not dispense the exact volume in each test tube.
3) option B. use a new DP to remove some reaction solution before each addition.
4) option D. if amylase concentration were zero, digestion of starch would require much longer time.