This experiment makes use of plants having variegated leaves (leaves in which in some parts chlorophyll is absent). The following figure shows an example of such plants.
PROCEDURE
PROCEDURE
- Destarch a potted plant with variegated leaves.
- Choose a leaf and make a simple drawing of the leaf showing clearly the regions which are green in colour as well as the regions which are not green in colour.
- Expose the plant to bright sunlight for 2 hours.
- After 2 hours removed the pre-chosen leaf and test it for the presence of starch using Iodine solution.
OBSERVATION
- Iodine solution changed to blue-black only in the green regions of the leaf whereas the Iodine solution remain unchanged in the non-green regions.
CONCLUSION
- Chlorophyll (in the green regions) is needed by green plants to photosynthesize.
