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प्रश्न
Are the following statement true or false? Give a reason in support of your answer.
Destarching of the leaves of a potted plant can occur only at night.
पर्याय
True
False
उत्तर
This statement is false.
Explanation:
Destarching of the foliage of a potted plant can occur not only at night but also when the plant is exposed to continuous darkness for a specific period. This process can be occur in the absence of light and entails the removal of stored starch.
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संबंधित प्रश्न
A healthy oat seeding in a pot is transferred from light to any airy but completely dark room. How would it differ from its original condition in appearance after about a week? Explain the difference.
Two healthy green plants were placed in the dark for 24 hours. They were then set up, as shown in the figure, for 4 hours. Then a leaf was taken from each plant and
the chlorophyll was removed from the leaves:
( i) What is the next and final step in this experiment?
( ii ) What would be the results of the final step?
( iii ) Why was it necessary to grease the glass sheet?
( iv ) What hypothesis is being tested in this experiment?
Mention one difference between the following on the basis of what is given in bracket.
Chlorophyll and chloroplast (part of plant cell)
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)
Photosynthesis in green plants is directly and indirectly dependent on so many plant structures.
Explain briefly the role of the following structures in this process Guard cells.
Given alongside is the diagram of an experimental set-up:
- What is the objective of this experiment?
- Will it work satisfactorily? Give reason.
- What alteration(s) will you make in it for obtaining expected result?
- Would you take any steps before starting the experiment? Describe this step and explain its necessity.
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.
During the starch test, why was the leaf
(1) boiled in water
(2) boiled in methylated spirit
Match the terms given in column A with column B:
| Column A | Column B | ||
| (a) | Chlorophyll | (i) | Removes/absorbs CO2 |
| (b) | Methylated spirit | (ii) | Tests presence of starch |
| (c) | Potassium hydroxide | (iii) | Traps solar energy |
| (d) | Iodine solution | (iv) | Produces oxygen |
| (e) | Water | (v) | Bleaches chlorophyll |
