Originally posted on February 3, 2010
A demonstration to magnify the process of photosynthesis.
A large green mixing bowl
2 zip-top bags
1 labeled “O2”
1 labeled “CO2”
Water (in a cup)
Before class begins, inflate each of the bags (blow them up and quickly seal them). Place the bag of O2 and the sugar inside the green mixing bowl. Don’t let the students see the inside of the bowl.
For the demonstration:
Photosynthesis takes place in the chloroplasts, represented by the large green bowl. Ask for volunteers to name the “ingredients” needed for photosynthesis: CO2 and water. As the reactants are named, add each to the mixing bowl (I pour the water in and empty the contents of the CO2 bag into the bowl). Photosynthesis also requires the presence of light, so shine the flashlight into the bowl while you give it a stir. Ask for volunteers to name the products made during photosynthesis: O2 and sugar. As each of the products are named, pull them out of the mixing bowl.