Enzymes Answer the following questions 1.In the reaction with urease, what does an increase in pH represent? It represent alkalin- enving 2. In the urease reaction, why does the pH increase and then remain constant after a period of time? 3. What does incubating urea at 100 °C do? 4. Design an experiment or experiments, to determine why the pH of the reaction with urease remains constant after a period of time. 5. What kind of mammalian tissue would be a good source of the enzyme urease? 6. Would you expect elasmobranchs to have high concentrations of the enzyme urease in their tissues? Explain. 7. Design an experiment to determine, within 0.1 pH units, the pH optima of the enzyme pepsin. 8. How does pepsin digest proteins? 9. Would you expect pepsin to be active in the anterior small intestine? 10. What is the purpose of incubating the film strips with water? 11. What was the point of performing the positive controls in the alpha amylase experiment? Would they have to be done everytime the experiment was performed? 12. In the alpha amylase experiment, is it possible to get a negative starch and a negative reducing sugar test in the same assay? 13. Why was it necessary to equilibrate the solutions to the proper temperature in the alpha amylase experiment? Why wasn't it done in all of the experiments? 14. Do you think the alpha amylase experiment was properly controlled? What other controls could or should have been done? 15. Which test is the more sensitive assay for alpha amylase activity, the IKI test or the reducing sugar test? Explain why you chose your answer. 16. Is it possible for an enzyme to be unaffected by increasing temperature while still observing a decrease in rate of reaction with increasing temperature? Describe some conditions under which this might occur.