Question

A learner wanted to find out if starch was present in both leaves grown in direct sunlight and leaves grown in the shade
Plan an investigation to determine if starch is present in both types of leaf

Answer 1

Answer:

The leaf of the potted plant was covered with a piece of black cloth to destarch it. Potassium hydroxide solution is to absorb the carbon dioxide gas from the air present in the glass bottle so that no carbon dioxide is left in the air inside the glass bottle. He will find that the leaf which was inside the glass bottle having no carbon dioxide around it, does not turn blue on adding iodine solution showing that no starch is present in this leaf. From this observation, we conclude that the photosynthesis to make starch in the leaf does not take place without carbon dioxide. And by covering the flask containing leaf B with black cloth, the leaf wont get exposure of sun light and photosynthesis won't happen. From this observation, we conclude that photosynthesis (to make starch) takes place in the presence of sunlight. Hence both the leaves do not have starch.

Explanation: