Digestive System (Grade 10)

Activity Language
Grade
Time Needed for Activity
Students model the digestive system, learning about some of the digestive enzymes and physiology along the way.

What You Need

Activity 1: Travelling Through the Digestive System

Per Class Per Pair of Students
2 plastic cups (one for "bile" and one for "saliva" 1 piece of table cloth cut the size of a desk
1 disposable pipette 1/3 of a banana
Green food colouring 2 graham crackers
Photo showing the digestive system 1 plastic ziploc bag
Paper towel roll or napkins 1 Dixie-type cup (3 oz.) with a hole in the bottom
  1 leg of a pair of pantyhose (open at one end and closed at the toe end).
  1 Dixie-type cup with no hole in the bottom 

 

Activity 2: Creating a Paper Artwork of the Digestive System

Supplies
Glue and Scissors
Cardstock with digestive system parts and white cardstock

 

PowerPoint:

Guide:

 

Safety Notes

As a Let’s Talk Science volunteer, safety must be foremost in our minds during all activities. As STEM role models, volunteers must always also model safe science practices.

Always keep in mind the following precautions:

  • Emphasize and demonstrate appropriate safety procedures throughout the presentation.
  • Be professional but have fun.
  • Keep workspaces clean to avoid tripping hazards.
  • Allergens should have been checked before reserving the kit (e.g. allergies to latex).

What To Do

Pre-Activity Preparation

Ask the teacher to:

  • Make bile by adding a few drops of green food colouring to one of the plastic cups, then add about 1/2 full of water (place the pipette near or in this cup)
  • Fill the 2nd plastic cup with 3/4 cup of water (saliva)
  • Fill each paper cup (the ones without the hole in the bottom) about 2/3 full of water
  • Cut bananas into 3 or 4 – enough for each pair to have 1/4 - 1/3 of a banana
  • Place a piece of tablecloth on each pair of students desk.
  • Distribute to each pair of students – one paper cup with a hole in the bottom; one paper cup 1/2 filled with water; one pantyhose leg, 1 plastic baggie, 2 graham crackers; piece of banana
  • Students need to take out a pair of scissors per pair

Activity 1: Travelling Through the Digestive System

Complete this activity over a table cloth to help with clean-up.

  1. Have the students ‘chew’ the graham cracker (1 per person), by placing it in their hand and squishing it. They should keep the cracker bits in their hand just as they would their real mouth. As they are doing this, have the teacher pour a bit of water (saliva) into each of their hands as they are ‘chewing’. They should end up with a ball of food (bolus) when they are done ‘chewing’ just like we do in our mouths. Remind them or ask them what food type starts to break down in the mouth [carbohydrates].
  2. Have them put the banana, both of their chewed-up graham crackers, and the water from the cup (stomach acid) into the bag (stomach). Have them seal the bag tightly without much air in the bag.
  3. Have them smush up the food and water in the stomach (until it’s fairly liquid and no big chunks). Remind them to be careful not to break the bag.
  4. Have them cut a hole in the bottom of the bag (valve called the pyloric sphincter), and pour it into only the top 1/3 of the panty hose leg. This will take 2 people. One cuts the hole in the bag and the other holds the panty hose leg open and places their other hand to keep the food going through the whole leg. When they have the food in the top 1/3 of the panty hose leg, ask the teacher to add the bile (green food coloured water) using the pipette. You can let them know the teacher is squirting in bile which helps to break down fats (like dish washing detergent does on our dishes). Also remind them again that most of the digestion takes place here.
  5. Have them squeeze the food through the pantyhose – it’s messy (representing the small intestines and the liquid coming out of the stocking represents the nutrients going to the rest of the body).
  6. Have the students cut valve (ileocecal sphincter), so the food can go into the large intestine (cup with the hole in it) and squeeze the food into the cup (representing the large intestine).
  7. Have the students close the top of the cup and squeeze their waste through the hole (anus/anal sphincter) and poop out the undigested food onto the table cloth!

Activity 2: Creating a Paper Artwork of the Digestive System

Pass out 1 piece of white cardstock and one of each of the paper digestive system parts. Instruct students to cut these out and glue them to the paper in the proper place. They can label each organ and write something that the organ does (if time). You could have the PowerPoint slide up for this.

 

Discovery

Investigate Further

We usually do this activity along with the circulatory system activity as both are about 20-30 minutes long. See Related Activities below.

Investigate Further

We usually do this activity along with the circulatory system activity as both are about 20-30 minutes long. See Related Activities below.

Resources

PowerPoint:

Guide: