10
Do as directed.
(1) How will you make China rose (jasudpatra) using materials found around you?
(2)How will you make anemometer using materials found around you? How will you use it?
Answers
Explanation:
Strips of black paper, destarched potted plant and iodine solution - These are the requirements of experimental set up to show that light is necessary for photosynthesis.
Procedure for the experiment:
1. Take the potted plant and keep it in a dark place for 2-3 days so that the leaves get destarched.
2. Cover a part of one of its leaves with the strip of black paper. Make sure that you cover both the sides of the leaf.
3. Now place this plant in sunlight for 3—4 hours.
4. Pluck the selected covered leaf and remove the black paper covering it.
5. Place this leaf in the beaker containing water and boil it for about 10 minutes.
6. Take out the leaf and now boil it in alcohol, using the water bath, for 10 minutes. This removes the chlorophyll.
7. Take out the leaf and wash it under running water.
8. Place this leaf in the Petri dish and put a few drops of iodine solution on it. Now observe the change in colour.
Observation: The leaf turns blue-black except in the covered region. As this covered region did not receive light, photosynthesis did not occur. Hence no starch was formed there. The uncovered region received light and starch was formed there due to photosynthesis.
solution