write an experiment to show that sunlight is necessary for photosynthesis.

For the answer of your query you may refer to the study material (Science practicals--- Practical no. 9) on our website at the following link

http://cbse.meritnation.com/study-online/study-material/ZkUEoUTTUnPuwG1oGvgDEQ!!/Rcx96cIdZuF@sPwACGo6Wg!!

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Aim: To show that light is necessary for photosynthesis.

Apparatus and Materials: well watered destarched potted plant(plant kept in dark for some time so that all the starch in it gets consumed) , dark paper, scissors / knife / scalpel, pins/clips

Method / procedure:The set up is as shown below:-

Fix the paper on one of the leaves as shown in the diagram below.

- The experimental set up is exposed to sunlight for 2-6 hours. The p[art of the leaf which is covered will not receive sunlight.

- The paper is removed and the leaf is tested for starch with iodine solution. The area that turns blue black shows presence of starch.

- Make a labelled diagram to show the results.

Results.

Conclusion.

Starch is produced only in areas that received light, showing that light is necessary for photosynthesis.

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 Aim: To show that light is necessary for photosynthesis.

Apparatus and Materials: well watered destarched potted plant(plant kept in dark for some time so that all the starch in it gets consumed) , dark paper, scissors / knife / scalpel, pins/clips

Method / procedure:The set up is as shown below:-

Fix the paper on one of the leaves as shown in the diagram below.

- The experimental set up is exposed to sunlight for 2-6 hours. The p[art of the leaf which is covered will not receive sunlight.

- The paper is removed and the leaf is tested for starch with iodine solution. The area that turns blue black shows presence of starch.

- Make a labelled diagram to show the results.

Results.

Conclusion.

Starch is produced only in areas that received light, showing that light is necessary for photosynthesis.

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 thanks!!!!! :)

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Green plants prepare their food through the process of photosynthesis using carbon dioxide and water in the presence of sunlight and chlorophyll.

Experiment to demonstrate that sunlight is essential for photosynthesis

Place a healthy green potted plant in a dark room for 1-2 days. This is done to ensure that the plant consumes all its reserve food and the leaves do not contain any starch. Then, cover a portion of a leaf of this plant on both sides with two uniform pieces of black paper, fixed in position with two paper clips.

Now, expose this plant to bright light. After a few hours, remove the leaf, decolourize it with alcohol, and test the presence of food (starch) with iodine solution.

You will observe that the portion of the leaf covered with black paper does not show any presence of starch (food).

Explanation of the experiment:

The food prepared by plants (carbohydrates) through the process of photosynthesis is stored as starch. This starch reacts with the iodine solution to change to blue-black colour. Only those portions of the leaf that were exposed to sunlight could photosynthesize and hence, change to blue-black colour when tested with iodine.

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THANKS ALOT....!!!!!!!!!
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THANKS ALOT!!
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THANKS ALOT
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thanks vyankatesh mule
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Objective:

To show experimentally that light is essential for photosynthesis.

 

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Apparatus and materials required:

A healthy potted plant, a petri dish, a beaker containing water, forceps, a water bath, a piece of wire gauze, a tripod, a burner, a box of matches, alcohol a strip of black paper, iodine solution and clips.

Theory:

Photosynthesis is a biochemical process by which green plants s5mthesize simple sugar in the presence of sunlight using carbon dioxide from the atmosphere and water from the soil. This simple sugar (glucose) is later converted to starch.

6CO2 + 12H2O ChlorophyII / Sunlight C6H12O6 + 6H2O + 6O2

 

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The most important factor for photosynthesis is light. The rate of photosynthesis depends on the quantity and quality of light. The chlorophyll molecule in green leaves absorb light, get excited and emit electrons. The emitted electrons are used in the production of adenosine triphosphate (ATP). Finally the solar energy is converted into chemical energy and stored in the glucose produced.

The rate of photosynthesis is the maximum in the presence of red and blue lights, while in green light the rate is minimum because green light is reflected by the chlorophyll molecules.

Procedure:

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.

Observations:

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.

Result:

Light is essential for photosynthesis

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thanku
 
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Experiment: Objective:

To show experimentally that light is essential for photosynthesis.

Apparatus and materials required:

A healthy potted plant, a petri dish, a beaker containing water, forceps, a water bath, a piece of wire gauze, a tripod, a burner, a box of matches, alcohol a strip of black paper, iodine solution and clips.

Theory:

Photosynthesis is a biochemical process by which green plants s5mthesize simple sugar in the presence of sunlight using carbon dioxide from the atmosphere and water from the soil. This simple sugar (glucose) is later converted to starch.

6CO2 + 12H2O ChlorophyII / Sunlight C6H12O6 + 6H2O + 6O2

The most important factor for photosynthesis is light. The rate of photosynthesis depends on the quantity and quality of light. The chlorophyll molecule in green leaves absorb light, get excited and emit electrons. The emitted electrons are used in the production of adenosine triphosphate (ATP). Finally the solar energy is converted into chemical energy and stored in the glucose produced.

The rate of photosynthesis is the maximum in the presence of red and blue lights, while in green light the rate is minimum because green light is reflected by the chlorophyll molecules.

Procedure:  

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.

Observations:

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.

Result:

Light is essential for photosynthesis.

Precautions:

1. Before starting the experiment, the leaf must be distracted.

2. The leaf must be covered with black paper properly to prevent the entry of light.

3. Boiling the leaf in alcohol should be done in the water bath.

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Please find this answer

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Objective:

To show experimentally that light is essential for photosynthesis.

?

Advertisements:

Apparatus and materials required:

A healthy potted plant, a petri dish, a beaker containing water, forceps, a water bath, a piece of wire gauze, a tripod, a burner, a box of matches, alcohol a strip of black paper, iodine solution and clips.

Theory:

Photosynthesis is a biochemical process by which green plants s5mthesize simple sugar in the presence of sunlight using carbon dioxide from the atmosphere and water from the soil. This simple sugar (glucose) is later converted to starch.

6CO2?+ 12H2O ChlorophyII / Sunlight C6H12O6?+ 6H2O + 6O2

?

Theory:

The most important factor for photosynthesis is light. The rate of photosynthesis depends on the quantity and quality of light. The chlorophyll molecule in green leaves absorb light, get excited and emit electrons. The emitted electrons are used in the production of adenosine triphosphate (ATP). Finally the solar energy is converted into chemical energy and stored in the glucose produced.

The rate of photosynthesis is the maximum in the presence of red and blue lights, while in green light the rate is minimum because green light is reflected by the chlorophyll molecules.

Procedure:

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.

Observations:

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.

Conclusion:

Light is essential for photosynthesis
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