Question

What is the role of bioling water and bioling alcohol
in experiment of light is necessary for photosynthesis

Answer 1

This procedure (boiling alcohol) kills a leaf, disrupts the cell membranes and softens the cuticle and cell walls. This makes it possible to extract the chlorophyll with hot ethanol and also allows the iodine solution to penetrate the cells and react with any starch present.

Boiling water -The hot water kills the leaf and the alcohol breaks down the chlorophyll, taking the green color out of the leaf. When you put iodine on the leaves, one of them will turn blue-black and the other will be a reddish-brown. Iodine is an indicator that turns blue-black in the presence of starch.

Answer 2

Answer:

Alcohol being inflammable may catch fire if boiled directly over the flame. Black paper is used to cover the leaf as it is a good absorber of light and blocks the entry of light to the leaf and hence no photosynthesis occurs in the covered portion.

Explanation:

We boil the leaf in alcohol when we are testing it for starch because to remove the green pigment chlorophyll present in it. For the starch test, we need to observe the colour change from brown to blue when iodine is put on the leaf. But, initially the leaf is green in colour which does not show the required observation. Hence to remove the green pigment present in the leaf we boil the leaf in alcohol when we are testing it for starch.