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प्रश्न
Two potato cubes each 1 cm3 in size, were placed separately in two containers (A and 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 somewhat decreased in size. Use the above information to answer the questions that follow:
Name and define the physical process being investigated in this experiment.
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उत्तर
The process being investigated is osmosis. Osmosis is the diffusion of water molecules across a semi-permeable membrane from a more dilute solution (with a lower solute concentration) to a less dilute solution (with a higher solute concentration).
संबंधित प्रश्न
Osmosis and diffusion are the same except that osmosis there is:
The space between the cell wall and plasma membrane in a plasmolysed cell is filled with ______.
The following diagram represents a plant cell after being placed in a strong sugar solution.
Guidelines 1 to 5 indicate the following
(1)Cell wall, (2) Strong sugar solution, (3) Protoplasm (4) Large vacuole, (5) Nucleus
(1)What is the state of the cell shown in the cell shown in the diagram?
(2)Name the structure which acts as a selectively permeable membrane.
(3)If the cell had been placed in distilled water instead of strong sugar solution, which feature would not have been seen?
(4)Name any one feature of this plant cell which is not present in an animal cell.
Explain why:
The leaves of wilted lettuce, if kept in cold water, become crisp.
Choose the correct answer:
Osmosis involves diffusion of ___________
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:
Redraw in the space provided, the diagram of the cell if it is soon placed in ordinary water for some time.
In the figure below ‘A’ shows a cell in the normal state and ‘B’ shows the same cell after leaving it in a certain solution for a few minutes.
(i) Describe the change which has occurred in the cell as seen in B.
(ii) Give the technical term for the condition of the cell as reached in B and as it was in A.
(iii) Define the process which led to this condition.
(iv) What was the solution-isotonic, hypotonic or hypertonic, in which the cell was kept?
(v) How can the cell in B, be brought back to its original condition?
(vi) Name the parts numbered 1 to 3.
The diagram given below is of an experiment just at the start. Study the diagram carefully and answer the following questions :
(i) What does the experiment demonstrate?
(ii) Define, the process demonstrated in the experiment.
(iii) What changes are observed after a few hours?
(iv) Give two examples of a semi-permeable membrane.
(v) Which limb of the U-tube contains a more concentrated sucrose solution, A or B?
(vi) Why is the membrane separating the two solutions labeled as semi-permeable membrane?
The beaker is divided into two chambers A and B. The big circle represents solute and the small circles solvent.
(i) What can you say about the size of the holes in the membrane, if it is to behave semi- permeably between these two?
(ii) Will the solvent molecules pass through the membrane from left to right, from right to left, in either direction or in both directions?
(iii) In which direction will there be a net movement of solvent molecules?
Fill in the Blank
Raisin swells up when kept in a __________ solution.
