Name Class Date

30.3 The Digestive System

1. What is the function of the organs of the digestive system?

Follow the directions.

1. Use terms from the box to complete the steps in the flowchart of digestion.

2. In the boxes to the right of the flowchart, describe what is happening at each step.

Name Class Date

Absorption and Elimination

The inner surface of the small intestine is covered with circular folds. The folds are covered with fingerlike parts called villi (singular: villus). Each villus holds blood and lymph vessels. They absorb nutrients and carry them to the body. The diagram to the left shows the circular folds on the wall of the small intestine. The diagram to the right shows a villus.

Follow the directions.

1. Use the words below to label the diagrams.

Answer the questions.

2. How is the small intestine well-adapted for its function?

3. What is the primary function of the large intestine?

4. What happens to waste materials when they leave the colon?

5. What role does the large intestine play in maintaining homeostasis?

27.1 Feeding and Digestion

Heading / Details
Obtaining Food / Animals can be filter feeders, detritivores, carnivores, herbivores, or nutritional symbionts.
Processing Food
Specializations for Different Diets

Processing Food

4. How is the digestion of food different in simple animals compared with more complex animals?

5. How is a one-way digestive track like a “disassembly line”?

6. Label the digestive structures of this cnidarian.

Specializations for Different Diets

The visual analogy compares different types of teeth with common tools. Complete the table about the different kinds of teeth found in mammals and the tools they are like.

Teeth Adaptations in Mammals
Type of Teeth / Description / Tool Analogy
Canines
chisel-like teeth used for cutting, gnawing, and grooming
Molars

7. Find a partner. Using the analogy, explain to your partner the kinds of specialized teeth in your own mouth.

8. Explain whether organisms with a gastrovacular cavity or organisms with a digestive tract obtain and process nutrients more efficiently.