Assessing Lipase Digestion of Fat

11/11/2019 PhysioEx Exercise 8 Activity 4 PhysioEx Lab Report Exercise 8: Chemical and Physical Processes of Digestion Activity 4: Assessing Lipase Digestion of Fat Name: Date: 11 November 2019 Pre-lab Quiz Results You scored 100% by answering 4 out of 4 questions correctly. 1 Which of the following is/are true of bile? You correctly answered: It works by a physical process. 2 The substrate used in this simulation is You correctly answered: vegetable oil. 3 When fatty acids are liberated by lipase, the pH You correctly answered: decreases. 4 One of the products of the chemical digestion of lipids is You correctly answered: fatty acids. Experiment Results Predict Question 1 Predict Question: Which tube do you think will have the highest lipase activity? Your answer: tube 3 (lipase, deionized water, bile salts, pH 9.0 buffer). Stop & Think Questions 1 What does the pH measure? You correctly answered: both lipase activity and fatty acid release. 2 Why is it difficult to detect whether lipase is active in tube 5 (lipase, vegetable oil, bile salts, pH 2.0 buffer)? You correctly answered: The pH is already very low, so a decrease in pH might be difficult to detect. Experiment Data 1/3 11/11/2019 PhysioEx Exercise 8 Activity 4 Tube No Reagent 1 Reagent 2 Vegetable Oil Reagent 3 1 Lipase 2 Lipase Vegetable Oil Deionized Water 3 Lipase Deionized Water Bile salts 4 Deionized Water 5 Lipase 6 Lipase Reagent 4 pH 7.0 Buffer Time (min) Temp (°C) pH 60 37 6.21 pH 7.0 Buffer 60 37 6.21 pH 9.0 Buffer 60 37 9.00 Bile salts pH 7.0 Buffer 60 37 7.00 Vegetable Oil Bile salts pH 2.0 Buffer 60 37 2.00 Vegetable Oil Bile salts pH 9.0 Buffer 60 37 8.97 Vegetable Oil Bile salts Post-lab Quiz Results You scored 100% by answering 4 out of 4 questions correctly. 1 What is the product of lipase hydrolysis? You correctly answered: fatty acids. 2 From your results, which pH is ideal for pancreatic lipase digestion? You correctly answered: pH 7.0. 3 Which tube confirms that there is no lipase in bile salts or vegetable oil? You correctly answered: tube 4 (deionized water, vegetable oil, bile salts, pH 7.0 buffer). 4 From your results, where (based entirely on pH) would pancreatic lipase be active? You correctly answered: mouth and pancreas. Review Sheet Results 1 Explain why you can't fully test the lipase activity in tube 5 (lipase, vegetable oil, bile salts, pH 2.0 buffer). Your answer: The lipase activity in tube 5 cannot be fully tested because the pH is already low in tube 5 and measuring the lipase activity would decrease the pH more. 2 Which tube had the highest lipase activity? How well did the results compare with your prediction? Discuss possible reasons why it may or may not have matched. 2/3 11/11/2019 PhysioEx Exercise 8 Activity 4 Your answer: After completing the experiment it was identified that the tube with the highest lipase activity would be tube 1, this is because it has the closet pH to the intestines. It did not match my previous answer because I did not know the pH of the intestines. 3 Explain why pancreatic lipase would be active in both the mouth and the pancreas. Your answer: Pancreatic lipase would be active in both the mouth and pancreas it has the highest active activity in areas with a pH of 7.0, like the mouth and pancreas. 4 Describe the process of bile emulsification of lipids and how it improves lipase activity. Your answer: The process of bile emulsification of lipids occurs due to bile physically breaking up the fat globules. It improves lipase activity because of it breaking it down physically and not chemically. 3/3