Chemical and Physical Processes of Digestion free essay sample

Review Sheet Exercise 8 Chemical and Physical Processes of Digestion NAMEDane Wilson LAB DATE/TIMEaugust 4th Carbohydrate Digestion The following questions refer to Activity 1: Assessing Starch Digestion by Salivary Amylase. 1. At what pH did you see the highest activity of salivary amylase? Why? 7. 0 because that is when the salivary is most effective and it breaks down carbohydrates. 2. How do you know that the amylase did not have any contaminating maltose? We used a negative control to see if there is any amylase in the maltose. . What effect did boiling have an enzyme activity? Why? Boiling denatured the enzyme because it destroys the structure of the protein. 4. Describe the substrate and the subunit product of amylase. The substrate is starch the subunit is reducing sugar. The following questions refer to Activity 2: Assessing Cellulose Digestion. 5. Does amylase use cellulose as a substrate? Explain. No because amylase only works on starch and wont digest cellulose. We will write a custom essay sample on Chemical and Physical Processes of Digestion or any similar topic specifically for you Do Not WasteYour Time HIRE WRITER Only 13.90 / page 6. Did freezing have an effect on the activity of amylase? Explain. Freezing does not change the structure of the enzyme so it doesn’t have effect on the activity. 7. Do you think that the bacterial suspension contained the enzyme cellulose (an enzyme that digests cellulose)? Why or why not? Yes I think the bacteria contained cellulase because it specifically digests cellulose. Protein Digestion by Pepsin The following questions refer to Activity 3: Assessing Protein Digestion by Pepsin. 8. What is the substrate of peptidase? Explain, based upon your results. The substrate is a synthetic protein called APNA. . At which pH did you see the highest activity of pepsin? How does this correlate to the location of pepsin in the body? 2, it correlates well with the gastric environment. 10. What effect did boiling have on pepsin? Boiling the pepsin denatures the enzyme. 11. Was there any digested APNA contaminating the pepsin or deionized (DI) water? How can you tell? No there wasn’t any APNA contaminating either the pepsin or deionized water be cause negative spectrophotomer result. 12. What is the substrate in this experiment? What is the usual substrate for pepsin, and what subunits are formed with pepsin activity? APNA the usual is protein and the subunits are amino acids. 13. What was the effect of decreasing the incubation time on the optical density results? Decreasing incubation time causes decreased optical density. 14. What effect would decreased incubation temperature have on pepsin activity? Why? It would cause reduced optical density because the decreased rate of enzymatic. 15. What was the significance of using 37Â °C for the incubation? Because 37 C is body temperature. Fat Digestion by Pancreatic Lipase and the Action of Bile The following questions refer to Activity 4: Assessing Fat Digestion by Pancreatic Lipase and the Action of Bile. 16. Describe the activity of lipase with and without the addition of bile salts. Refer to Chart 4 for pH values. The lipase is more effective with the bile salts. 17. Is the activity of bile a chemical or physical process? Explain. Physical because it breaks up the fat. 18. What pH resulted in the maximum pancreatic lipase activity? 7. 0 How does this optimal pH correlate to the enzyme’s location in the body? It correlates with the duodenum. 19. Explain whether or not we can determine fat hydrolysis in tube 5. Why or why not? We can determine fat hydrolysis because we know the ph and there is no decrease. 20. What is the substrate in this experiment? What subunits does lipase form? The substrate are fats or vegetable oil the subunits formed fatty acids. Physical Process: Mechanisms of Food Propulsion and Mixing The following questions refer to Activity 5: Studying Mechanisms of Food Propulsion and Mixing: Deglutition (Swallowing). 1. Explain the significance of the movement of the tongue during swallowing. Because it prevents water from entering the airway 22. Describe three events that occur during the pharyngeal-esophageal phase of deglutition. The mouth nasopharynx and larynx are blocked the esophageal sphincter relaxes to open the esophagus and food moves through the esophagus by pressure gradients made by peristalsis. 23. What was the time interval that you recorded between the first and second sound?