Question

In the following experiment for photosynthesis, a leaf is inserted into a conical flask containing potassium hydroxide. What is the aim of the experiment?

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• A. To prove that oxygen is given out during photosynthesis
• B. To prove that carbon dioxide is given out during photosynthesis
• C. To prove that oxygen is produced during photosynthesis
• D. To prove that carbon dioxide is needed for photosynthesis

Answer 1

The correct option is D

To prove that carbon dioxide is needed for photosynthesis

From this observation, we conclude that carbon dioxide is necessary for photosynthesis. We will find that the lower half part of the leaf (which was inside the glass bottle having no carbon dioxide around it) does not turn blue-black on adding iodine solution showing that no starch is present in this lower half of the leaf.