BI 231 - Human Physiology and Anatomy
Digestive System Study Guide

Compiled by Linda Cram, Pat Bowne, Sherry Dollhopf, and Justin LaManna, 2007-11


The digestive tract is responsible for taking in food (ingestion), breaking it down into molecules small enough to be transported in the blood (digestion), and passing it into the blood (absorbtion). Accessory digestive organs help produce secretions needed for digestion. The liver is also responsible for converting absorbed foods into the forms needed by the cells of the body, and the pancreas controls cells' ability to pick food up from the blood.

All together, the digestive organs control how food gets from your lips to your hips!
Before class, make sure you: Understand what enzymes, proteins, carbohydrates, and fats are

Know the blood vessels of the hepatic portal system

Know the GI effects of the autonomic nervous system

Tutorials and reading assignment: Review digestion at:

Chapter 18  pp 620-654

Chapter 19 sec 19.3

What you should know for the assessment:

List the structures food passes through from mouth to anus, telling what compounds are digested in each structure and what enzymes are involved.

What are the three phases of digestion ? What makes each phase start, and what happens during each phase?

What are the major hormones involved in digestion? Where does each one come from, what causes it to be released, and what does it do?

How is fat digested and transported in the blood? What are the good and bad cholesterol?

What are the functions of the liver, and what would happen if the liver stopped working?

What is the exocrine pancreas, and what does it do? What would happen if it stopped working?

What is the endocrine pancreas? What does it do? What would happen if it stopped working?

List of terms to know about digestion

Terms to know about metabolism

Practice Questions 1.

Review questions 1-4, 6-14 on pp. 658

A woman ate a potato containing starch that had been labeled with radioactive C molecules. Two days later, she exhaled radioactive CO2 and radioactive glycogen was found in her liver. Explain every step that was involved in getting the radioactive starch from the potato she ate into her cells and broken down into CO2. Include digestion, absorbtion, anabolism and catabolism, and all relevant hormones and enzymes.

2. CREATE a flow chart to answer the following question.

A child has diabetes mellitus and cannot make insulin but he can make glucagon.  He comes into hospital with weight loss, high blood sugar, high levels of amino acids and fatty acids in his blood, high levels of ketones, heavy breathing, and dehydrated cells. How did his disease cause these problems?

Practice question with example answer

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