Question

How would you test the presence of starch in leaves?

Answer 1

• The presence of starch in leaves can be tested using iodine test.
• Procedure to test for the presence of starch in leaves:

1. Dip the leaf in boiling water for a few minutes. After this, immerse it in a beaker containing alcohol.

2. Carefully place the above beaker in a water-bath and heat till the alcohol begins to boil. This decolourises the leaf.

3. Now dip the leaf in a dilute solution of iodine for a few minutes.

4.On addition of iodine if the leaf changes its colour to blue-black then it shows the presence of starch in the leaves.