When testing a leaf for starch, why is it first placed in boiling water?
A. to extract the chlorophyll B. to remove colour from the leaf C. to dissolve the starch D. to stop chemical reactions
Correct Answer: D
Explanation
To test for the presence of starch in a leaf, the leaf is first placed in boiling water for half a minute to kill it; it is then decolourized in hot alcohol; followed by dipping in hot water to soften it. Iodine solution is then added. NB: killing the leaf means stopping the chemical reactions
