Materials required: A healthy potted plant, petri dish, wire gauze, tripod, bunsen burner, lighter, beaker containing water, forceps, a water bath, alcohol a strip of black paper, iodine solution and clips.
1. Take the potted plant and keep it in a dark place for 2-3 days to destarch the leaves
2. Cover a part of one of its leaves(both sides) with the strips of black paper.
3. Keep the plant in sunlight for 2-3 hours.
4. Pluck the covered leaf covered in black strip and remove the strip.
5. Light the burner and heat some water in a beaker.
6. Place this leaf in the beaker for about 5 minutes.
7. Take out the leaf and now boil it in alcohol, using the water bath, for 10 minutes.
8. Take out the leaf and wash it under running water.
9. Place this leaf in the Petri dish and put a few drops of iodine solution on it.
Notice the change in colour. The leaf changed into blue-black colour except the covered region of the leaf showing no photosynthesis had taken place in that region since it didn't receive any sunlight.