Describe the half-leaf experiment on photosynthesis.
- A potted plant is kept in the dark for 48-72 hours for destarching.
- A part of a leaf is enclosed in a test tube containing some KOH solution, and the other half is kept out exposed to air.
- It is made sure that the leaf does not break off from the plant body while the experiment is going on.
- The setup is then kept in sunlight for some time.
- Later, the leaf is tested for the presence of starch.
- The starch test shows that the exposed part of the leaf tests positive for starch, while the part in the test tube tests negative for starch.
- This shows that carbon dioxide is necessary for photosynthesis.