Boojho wanted to test the presence of starch in leaves- He performed the following steps-He did not get the expected result- Which step did he miss- Explain- -

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Byju's Answer

Standard VII

Biology

Photosynthesis

Boojho wanted...

Question

Boojho wanted to test the presence of starch in leaves. He performed the following steps.

He took a leaf and boiled it in water.

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

The following steps are to be followed while testing for starch:

Take a leaf in a beaker and boil the leaf. And pour spirit/alcohol to completely immerse the leaf in a test-tube.

Now, place the leaf in a beaker half filled with water.

Heat the beaker till all the green colour from the leaf comes out.

Take out the leaf carefully and wash it in water.

Place it on a watch glass and pour some iodine solution over it.

Boojho missed the step where he was supposed to
boil the leaf in alcohol.

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Boojho wanted to test the presence of starch in leaves.​ He performed the following steps.​ He took a leaf and boiled it in water.​ 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.

He took a leaf and boiled it in water.

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.