The digestive system

Studying historical experiments

Studying historical experiments

Slide

Objective

Illustrate that:

  • The enzymes within digestive juices dissolve food (chemical action).
  • Grinding up food beforehand (mechanical action) helps enzyme action.

 

Instructions:

Put the following in a bain-marie at 37°C:

  • test tube 1 containing a piece of meat and water;
  • test tube 2 containing a piece of meat and gastric juices;
  • test tube 3 containing a piece of minced meat and gastric juices.

test tubes english

Leave for two hours and then observe what has happened.

  • The meat in tube 1 remains intact.
  • The meat in tube 2 has dissolved.
  • The meat in tube 3 has dissolved more than the meat in tube 2. This is because it had been minced.