Question

How would you test the presence of starch in leaves?

Answer 1

1. Take a potted plant with variegated leaves – for example, money plant or crotons.
2. Keep the plant in a dark room for three days so that all the starch gets used up.
3. Now select a leaf cover its portion with a ***** strip paper and keep the plant in sunlight for about six hours.
4. Pluck the leaf from the plant. Mark the uncovered area in it and trace them on a sheet of paper.
5. Dip the leaf in boiling water for a few minutes.
6. After this, immerse it in a beaker containing alcohol.
7. Carefully place the above beaker in a water-bath and heat till the alcohol begins to boil.
8. Now dip the leaf in a dilute solution of iodine for a few minutes.
9. Take out the leaf and rinse *** the iodine solution.
   10 You observe that the presence of starch in various areas of the leaf which was uncovered.