Question

How can we decolorize a leaf? What will you conclude when white patches do not turn blue-black on adding iodine solution?

Answer 1

Decolorization of leaf:

1. The leaf color is due to various pigments present in cells, such as chlorophyll.
2. Upon boiling the leaves, the color of the leaves disappears as the pigments disappear.
3. Another method to decolorize is by boiling it with ethanol.
4. After boiling, the leaf should be left to rinse and then dried in a petri dish.
5. A few drops of iodine should be put on the leaf.
6. The iodine helps to identify starch on the leaves, as the blue-black color identifies starch present on leaves.
7. When white patches do not turn blue-black on adding iodine solution shows that white patches do not photosynthesize as iodine turns blue black in the presence of starch.