Question

How do you test the presence of starch in leaves ?

Answer 1

Hey Friend,

Iodine test is done for the leaf to test the presence of starch in it.

Here's  an activity to test a leaf for starch...

Procedure - 

1. Detach a leaf from a destarched plant and dip it in boiling water for 30 seconds. 
2. Boil the leaf in alcohol or methylated spirit in a water bath.
3. Take out the leaf when it has decolorized.
4. Dip it in boiling water to make it soft.
5. Spread the leaf on white tile and pour iodine solution over it.

Observation - 

Some parts of the leaf turn blue-black while some parts don't.

Inference -

The parts which contained starch turned blue-black whereas the parts which did not contain starch remained the same.

Hope it helps!