1.9 Extended Learning - Activities and Projects
NCERT Class 7 Science Textbook for Blind Students made Screen readable by Professor T K Bansal.
1. Project
Take a potted plant with broad leaves. Take two strips of black paper and cut out a small square in the centers. Cover a part of two leaves with these papers and secure them with paper clips (Figure 1.9). Keep the plant in sunlight for 2-5 days. Observe the difference in the colour of the covered and the uncovered portions on the leaf. Perform iodine test on this leaf. Did the two parts show different results? Now take the second leaf. Remove the strip and expose the covered part to the sunlight for 2-3 days and do the iodine test again. Describe your observations.
Figure 1.9 Experiment to test the occurrence of photosynthesis
2. Visit a greenhouse if there is one near your place. Observe how they grow plants. Find out how they regulate the amount of light, water and carbon dioxide to grow the plants.
3. Try growing a sweet potato just in water. Describe your experiment and observations.
You can read more on the following website: www.phschool.com/science/biology_place/biocoach/photosynth/overview.html