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प्रश्न
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.
(i) What aspect of photosynthesis was being tested?
(ii) Why was the plant placed in the dark before beginning the experiment?
(iii) During the starch test, why was the leaf
(1) boiled in water
(2) boiled in methylated spirit
(iv) Write a balanced chemical equation to represent the process of photosynthesis.
(v) Draw a neat diagram of a chloroplast and label its parts.
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उत्तर
(i) Light is required for photosynthesis.
(ii) Before beginning the experiment, the plant was kept in dark in order to destarch it, i.e. to remove the pre-existing starch from the storage organs.
(iii)
(1) The leaf was boiled in water to destroy enzymes so that further chemical changes do not take place in the leaf.
(2) The leaf was boiled in methylated spirit to dissolve chlorophyll.
(iv) Chemical equation for the process of photosynthesis:
6CO2+12H2O`"Light"/"Chlorophyll"`C6H12O6+6O2+6H2O
(v)Chloroplast:
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संबंधित प्रश्न
Give appropriate biological/technical terms for the following:
An apparatus that measures the rate of water uptake in a cut shoot due to transpiration.
Identify the odd one in each set : Transpiration, Photosynthesis, Phagocytosis, Guttation
Complete the following paragraph by filling in the blank (1) to (5) with appropriate words:
To test a leaf for starch, the leaf is boiled in water to (1) _________. It is then boiled in Methylated spirit to (2) ________. The leaf is dipped in warm water to soften it. It is placed in a petri dish, and (3) _____ solution is added. The region of the leaf which contains starch, turns (4) ________and the region while does not contain starch, turns (5) __________.
The diagram given below represents an experiment to prove the importance of a factor in photosynthesis. Answer the questions that follow :
What will you observe in the experimental leaf after the starch test?
The diagram alongside represents an experiment conducted to prove the importance of a factor in photosynthesis.
Study the same and then answer the questions that follow:
(i) Name the factor being studied in his experiment.
(ii) Why was the plant kept in a dark room before conducting the experiment?
(iii}Why was the experimental leaf then kept in
1. boiling water 2. methylated spirit?
(iv) Name the solution used to test for the presence of starch in the leaf.
(v) What will we observe in the experimental leaf at the end of the starch test?
(vi) Give a balanced chemical equation to represent the process of photosynthesis.
Are the following statement true or false? Give reason in support of your answer.
The starting point of carbon cycle is the release of carbon dioxide by animals during respiration.
Which one of the following is a primary producer?
Planting trees help in decreasing global warming.
The chemical reaction occurs during photosynthesis is ______.
State whether true or false. If false, correct the statement.
Plants lose water when the stomata on leaves are closed.
