Sample Lab Notebook –Chemical and Physical Processes of Digestion-Exercise 8

Name

Date

Class (Course and Section) 

Lab Exercise Name

Introduction:  In this lab we will see how different chemical processes occur as we observe how different enzymes digest different substrates and produce subunits.

Key Terms:  (found in bold in Lab Manual)

Please define all bold terms in your own words:

Enzymes

Catalysts

Hydrolases

Substrates

Salivary glands

Stomach glands

Pancreas

Liver

Small intestine

Pepsin

Lipase

Salivary and Pancreatic Amylase

Bile acids

Activity 1 and Activity 2– Assessing Starch Digestion by Salivary Amylase:

In this exercise, we will watch how salivary amylase (enzyme) works on a substrate starch and produces the subunits maltose and glucose.

Data:

Please submit Data for Activity 1 and 2.

Please answer the following questions

1. What ph allowed the highest amylase activity and why? Please explain.
2. What effect does boiling have on enzyme activity?
3. Would the amylase present in the mouth be active in the stomach? Please explain your answer.
4. Does amylase digest peptidase?
5. Did Amylase use cellulose as a substrate?

Summary:  Using the data above, I saw that (summarized results).  This happens because (explanation). 

Activity 3-: Protein Digestion by Pepsin

-In this exercise, we will observe the chemical digestion of proteins

Please record and submit Data for Activity 3.

Please answer the following questions:

1. Would pepsin be active in your mouth?
2. What location in the body does pepsin have the greatest activity?
3.  What are the substrate and the subunits used in this experiment?
4. What would happen if you decreased the incubation temperature to 0 degrees Celsius?
5. What effect did boiling have on pepsin activity?

Summary:   Please summarize your data and explain how temperature and ph affected protein digestion.

Activity 4: Assessing Fat digestion by Pancreatic Lipase and the Action of Bile

Please record and submit your data for activity 4.

Please answer the following questions:

1. At what ph, did lipase have the greatest activity?
2. Is the activity of bile a chemical or a physical process? Please explain.
3. What is the substrate in the experiment? What are the subunits?
4. What happens to enzyme activity if we boil the enzyme?

Summary:  Please summarize the data. Where did lipase have the greatest activity and please correlate this to temperature and ph.

Activity 5: Mechanisms of Food propulsion and Mixing: Deglutition (Swallowing)

Please answer the following questions: (No data needs to be submitted)

1. Explain the significance of the movement of the tongue during swallowing.

Describe three events that occur during the pharyngeal-esophageal phase