1. Warm Up
Objective: Scientists will describe the digestive system by analyzing the labs.
What is the topic?
What will you be doing?
Why is this important?
How will you know if you have done well?

2. Warm Up
Objective: Scientists will describe the digestive system by analyzing the labs.
What is the topic? Digestive system
What will you be doing? Analyze labs
Why is this important? Understand our body; future career choice
How will you know if you have done well? Able to describe the digestive system; completed work

3. Activity 1: Digestion in the Mouth
Materials: crackers, timer
Put a regular cracker in your mouth. Record taste, texture, and any other observations.

4. Activity 1: Digestion in the Mouth
Place a new cracker in your mouth and let it sit for 1.5 minutes before chewing. Answer the following:
What does it feel like initially?
What does it feel like after 1 minute has passed?
What does it feel like after 1.5 minutes have passed?
What does it feel like when you chew it?

5. Activity 1: Digestion in the Mouth
3. What was the main texture difference in your mouth between chewing right away and waiting 1.5 minutes? 4. How is mechanical digestion shown in this activity? 5. Besides safety concerns around choking, why does food need to be chewed first? 6. How is chemical digestion shown in this activity? 7. Where does digestion begin? How do you know?

6. Activity 1: Digestion in the Mouth
3. What was the main texture difference in your mouth between chewing right away and waiting 1.5 minutes? Crunchy/dry to mushy/moist 4. How is mechanical digestion shown in this activity? chewing 5. Besides safety concerns around choking, why does food need to be chewed first? Breaks into smaller pieces = more surface = better digestion 6. How is chemical digestion shown in this activity? Saliva has enzymes (amylase) which help to break down food 7. Where does digestion begin? How do you know? Mouth, because mechanical and chemical digestion takes place there

7. Activity 2: Digestion in a Bag
Take a cracker and place it in the baggie.
Add a small amount (~2 spoonfuls) of solution.
Close your bag.
Using your fingers, break the cracker into smaller pieces.
What does the solution represent?
What does the cracker represent?
What does the baggie represent?
What process does this represent?

8. Activity 2: Digestion in a Bag
Take a cracker and place it in the baggie.
Add a small amount (~2 spoonfuls) of solution.
Close your bag.
Using your fingers, break the cracker into smaller pieces.
What does the solution represent? saliva
What does the cracker represent? Any food
What does the baggie represent? mouth
What process does this represent? Mechanical and chemical digestion

9. Activity 2: Digestion in a Bag
Carefully open your bag and add a small amount (~2 spoonfuls) of vinegar. Close your bag and squish until all of the pieces are small.
What do you observe happening?
What does the vinegar represent?
What process is represented now?
What does the baggie represent now?

10. Activity 2: Digestion in a Bag
Carefully open your bag and add a small amount (~2 spoonfuls) of vinegar. Close your bag and squish until all of the pieces are small.
What do you observe happening? Answers may vary – bubbling, smaller / mushy pieces
What does the vinegar represent? Stomach acid
What process is represented now? Chemical digestion in stomach
What does the baggie represent now? stomach

11. Activity 2: Digestion in a Bag
6. Carefully drain the liquid contents in the bucket at your table. Do this by creating a small gap so that solids do not escape. Close your bag after you have completed this step.
What organ does the bucket represent?
What stage of digestion does this represent?

12. Activity 2: Digestion in a Bag
6. Carefully drain the liquid contents in the bucket at your table. Do this by creating a small gap so that solids do not escape. Close your bag after you have completed this step.
What organ does the bucket represent? Large intestine
What stage of digestion does this represent? Reabsorption of water in the large intestine

13. Activity 2: Digestion in a Bag
Put the sealed bag into the trashcan.
What does this act represent?
What organ does the trashcan represent?

14. Activity 2: Digestion in a Bag
Put the sealed bag into the trashcan.
What does this act represent? Storage of waste
What organ does the trashcan represent? rectum

15. Analysis
What organs of the digestion system were NOT represented in this activity? What do they do? How could you have incorporated them into this activity?
Finished? Complete yesterday’s work, stations activity, essay, or any work that you have turned in yet for my class.