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प्रश्न
An experiment was set up as shown in the figure given below . The twig in the diagram was intact on the plant and it was as such in sunlight for a few hours .
(i) What is the aim of the above experiment ?
(ii) Why was potassium hydroxide placed inside the conical flask ?
(iii) What test would you perform on the leaf inside the flask?
(iv) What is the expected result of the above test ?
(v) Is it necessary to similarly test on outer leaf also ? Giva a reason .
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उत्तर
(i) The aim of the experiment is to prove that CO2 is necessary for photosynthesis.
(ii) Potassium hydroxide absorbs CO2 from the surrounding. It is placed to remove CO2 within the conical flask.
(iii) The leaf inside the conical flask would be tested for the presence of starch by the application of iodine.
(iv) The expected result of the above test is - No change in the colour will be observed.
(v) Yes, it is necessary to similarly test on the outer leaf also to show that leaves present in CO2 show photosynthesis.
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संबंधित प्रश्न
How would you demonstrate that green plants release oxygen when exposed to light?
Complete the following by filling the blanks 1 to 5 with appropriate words/terms/phrases:
To test the leaf for starch, the leaf is boiled in water to ______ (1). It is next boiled in methylated spirit to ______ (2). The leaf is placed in warm water to soften it. It is then placed in a dish and ______ (3) solution is added. The region which contains starch, turns ______ (4) and the region which does not contain starch, turns ______ (5)
Given below is the representation of a certain phenomenon in nature. With four organisms 1-4.
Name one natural element which all the organisms 2-4 and even 5 are getting from No. 1 for their survival.
Given alongside is the diagram of an experimental set-up:
Would you take any step before starting the experiment? Describe this step and explain its necessity.
A potted plant was taken in order to prove a factor necessary for photosynthesis. The potted plant was kept in the dark for 24 hours. One of the leaves was covered with black paper in the centre. The potted plant was then placed in sunlight for a few hours.
What aspect of photosynthesis was being tested?
Chlorophyll is necessary for photosynthesis.
ATP is needed for the dark reaction.
Give technical term:
Name only one plant, you are familiar with which has no chlorophyll.
Give reasons/explain:
During the starch test, the leaf is boiled in methylated spirit.
