NCERT Class 7 Chapter 1 Nutrition in Plants Suggested projects and activities
This activity asks us to cover a part of the leaf with black paper, compare the color with the uncovered part, and test with iodine solution.
The covered part of the leaf becomes light green and pale color. When we test them with iodine, the covered part does not turn blue.
When we cover a part of the leaf with paper, it can not photosynthesize and produce starch. Over time chlorophyll of the covered part translocates to other parts. As a result, the covered part becomes light green and pale. Iodine solution turns blue with starch. Since the covered part does not contain starch it does not turn blue.
This experiment demonstrates that sunlight is necessary for photosynthesis. For more details, you can visit this experiment.
2. Visiting a greenhouse farm.
A greenhouse farm is an artificial chamber that keeps plants warmer than the outside. For this, the chamber is made of glass or plastic that allows solar radiation but prevents its escape. Desired temperature and humidity are carefully controlled by fans and irrigation. This helps the vegetation to grow which is not possible in that area
3. Growing a sweet potato in water.
Sweet potato can be grown in water. For this, we dip a sweet potato into water. Within a few weeks, it sprouts, and a stem arises from it.