Gulp Gulp Digestion Lab Activity
Overview:
The students will follow food visually through a model of the digestive system. They
will discuss ways to move food more efficiently through the digestive system. This
lesson can be used to teach health, nutrition, or food - related topics.
Objectives:
The students will:
 describe parts of the digestive system,
 explain how food moves through the digestive system,
 discuss way to facilitate movement of food through the digestive system, and
 make observations and perform an experiment on the process of digestion.
Lesson Materials and Resources:
For each group of five students:
 Clear cup (represents the mouth)
 Fork (represents the teeth)
 Water (represents the saliva) found in yellow beaker
 Taped together cups (represents the esophagus)
 Ziploc bag (represents the stomach)
 Food (cereals) 3 types of cereal per experiment (students will measure out 1
tablespoon using small measuring cup for each of the cereals.
 Vinegar (represents the stomach acid) 30 ml. (students will measure this out into blue
beaker)
 Rolled paper towel that has been taped (represents the small intestine and colon)
 Pie pan
 Tape
 Small measuring cup
Conduct lab over pie pan to help with clean up.
Lesson Procedures:
1. Demonstrate or explain the experiment first and then have the students work in
groups. The students will mix food in plastic cup with a fork to demonstrate how
teeth grind up food. Students will break up the food into small pieces using their
fork.
2. The students will create a thick paste by adding a little water to the bowl to show
that the saliva mixes with the food. The students will observe and discuss what the
"saliva" does to the food.
3. The students will add 30 ml. of vinegar in a Ziploc bag.
4. The students will pour the mixture from the bowl through plastic cup “esophagus”
into the Ziploc bag, which represents the stomach. They will seal the bag.
5. The students will mash the food in the Ziploc bag. (Make sure bags are completely
closed and students do not push too hard) Have the students’ notice what is
happening. Have them describe what the "stomach acid" (vinegar) is doing to the
food.
6. Students will roll up a paper towel and tape it together. The students will snip one
corner of the Ziploc bag. The students will squeeze the mixture out of the Ziploc
bag into the rolled paper towel, which represents the small intestine and the colon.
Note how the paper towel is saturated and allows water to escape like the small
intestines. Finally the “waste” mixture will be squeezed into the pie pan.
7. Have the students describe what is happening to the food as it passes through the
intestines. (The liquid passes into the paper towel just as liquid nutrients are
passed into the blood stream.)
The solid food goes out the end of the rolled paper towel as waste, just as the solid
food goes out of the colon as waste in the digestive system.)
8. As the students perform the experiment, have them sketch and describe their write
observations of each step in an observation journal.
9. The students will share and discuss observations with the class. Have students
explain ways to move food more effectively through the digestive system (by
drinking sufficient amounts of water, eating fiber daily and engaging in physical
activity) and how this relates to good health.