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Question
Give scientific reasons : Balsam plants wilt during mid-day even if the soil is well watered.
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Solution
In case of balsam plants, the rate of transpiration during mid-day exceeds the rate of absorption of water by the roots. The cells therefore lose turgidity. In the evening or during the night, the stomata are constricted and the temperature is not very high; therefore, there is no loss of water through transpiration, and the turgidity of the leaves is re-acquired.
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RELATED QUESTIONS
The diagram given below represents a plant cell after being placed in a strong sugar solution. Study the diagram and answer the questions that follow:
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- Name the structure that acts as a selectively permeable membrane.
- Label the parts numbered 1 to 4 in the diagram.
- How can the above cell be brought back to its original condition? Mention the scientific term for the recovery of the cell.
- State any two features of the above plant cell which is not present in animal cells.
The diagram below represents a process in plants. The setup was placed in bright sunlight. Answer the following questions:
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Why was oil added to the water?
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Give Technical Term for the following.
A cell in a fully extended condition.
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The figure given below is a diagrammatic representation of a part of the cross-section of the root in the root hair zone. Study the same and then answer the questions that follow:
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- Xylem vessel, Soil particles, Root hair, Cortex respectively.
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