An interesting and memorable way of demonstrating digestion for Year 11 Human Biology.
Tuna sandwich made from one piece of bread and spread.
Length plastic tubing about 3.5cm x 20cm for the oesophagus
Medium plastic bag for the stomach.
Tubing about 7 to 10 cm in diameter, fashioned from a plastic bag, cut and taped together, 60 to 70 cm long to represent the small intestine.
Lengths of poppit beads to represent the fats, proteins, carbohydrates etc.
Water: represents the various enzymes.
Green liquid detergent-bile.
Chopping board or plate.
Knife.
Disposable gloves to prevent smelly hands.
Teacher explains the process of digestion from mechanical and chemical processes in the mouth through to the entry into the small intestine. Explain how the components of food are broken down by enzymes into smaller chains, as shown with the poppit beads
Chop up the sandwich on the board/plate, with the knife. What food groups does the sandwich contain?
Add a small amount of water (saliva).
Push bolus through the oesophagus into the stomach (plastic bag). Squish it together to represent the action of the stomach. Add water (acid, enzymes etc)
Transfer it into the plastic bag tubing (small intestine).
Add a squirt of green detergent (bile).