Question

after rinse the iodine solution what happen to color of leaf and compare this with tracing of the leaf done in begining . define from activity 6.1 class 10 bio​

Answer 1

answer - 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. The leaf that was in the light turns blue-black, which demonstrates that the leaf has been performing photosynthesis and producing starch.

explaination - Take a potted plant with variegated leaves for example, money plant or crotons.

Keep the plant in a dark room for three days so that all the starch gets used up.

Now keep the plant in sunlight for about six hours.

Pluck a leaf from the plant. Mark the green areas in it and trace them on a sheet of paper.

Dip the leaf in boiling water for a few minutes.

After this, immerse it in a beaker containing alcohol.

Carefully place the above beaker in a water bath and heat till the alcohol begins to boil

Now dip the leaf in a dilute solution of iodine for a few minutes.

Take out the leaf and rinse off the iodine solution.

Observe the colour of the leaf and compare this with the tracing of the leaf done in the beginning.