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प्रश्न
Explain why:
We gargle with saline solution in case of throat infection.
उत्तर
Saline water is hypertonic. So any infectious agent such as bacteria in the throat gets plasmolysed and this cures the infection.
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संबंधित प्रश्न
Movement of molecules of a substance from the region of their higher concentration to the region of their lower concentration without the involvement a separating membrane, is called
Two potato cubes each 1 cm3 in size, were placed separately in two containers (A&B), the container (A) having water and the other (B) containing concentrated sugar solution. After 24 hours when the cubes were examined, those placed in water were found to be firm and had increased slightly in size and those placed in concentrated sugar solution were found to be soft and had somewhat decreased in size. Use the above information to answer the questions that follow:
Account for the firmness and increase in the size of the potato cubes placed in water.
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The leaves of wilted lettuce, if kept in cold water, become crisp.
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A leaf cell of a water plant was placed in a liquid other than pond water. After sometime, it assumed a shape as shown below:
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Give Reasons for the following.
Salt and sugar are used in preserving food.
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(i) What would you do to bring this cell back to its original condition?
(ii) What scientific term is used for such condition?
(iii) Draw the same cell if it is kept in a strong sugar solution.
Multiple Choice Question:
Osmosis involves:
