Boojho wanted to test the presence of starch in leaves. He performed the following steps.
(1) He took a leaf and boiled it in water.
(2) He placed the leaf in a petri dish and poured some iodine over it.
He did not get the expected result. Which step did he miss? Explain.

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Solution

Firstly, the leaf has to be boiled in water followed by boiling in alchol so as to remove the green pigment of the leaf completely.

After boiling in alcohol, few drops of iodine solution is added.

But, boojho missed the step of boiling the leaf in the alcohol which removes the green pigment (chlorophyll), hence did not get the expected result (change in colour of leaf due to the presence of starch).

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Boojho wanted to test the presence of starch in leaves. He performed the following steps. (1) He took a leaf and boiled it in water. (2) He placed the leaf in a petri dish and poured some iodine over it. He did not get the expected result. Which step did he miss? Explain.

Boojho wanted to test the presence of starch in leaves. He performed the following steps.
(1) He took a leaf and boiled it in water.
(2) He placed the leaf in a petri dish and poured some iodine over it.
He did not get the expected result. Which step did he miss? Explain.