- Pick a leaf from a geranium exposed to light and one kept in the dark for 48 hours.
- keep the stem on the leaf grown in light
- remove the stem from the leaf grown in the dark
- Hydrolyze the cell walls of the geranium leaves by boiling in a water bath for 5 minutes until it looks like over-cooked vegetables)
- “Bleach“ the leaves by removing the pigments. Place the leaves in hot alcohol for 7 minutes until they turn white.
- Remove the leaves and place it in a petri dish.
- Add iodine to the dish. If starch is present, the leaf will turn a deep bluish-black color.
- Photograph the leaf with your phone to document the effects of light on carbohydrate storage.
