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Question
A thin strip of epidermal cells from the fleshy scales of an onion bulb was examined in a drop of water, under a microscope. All the epidermal cells looked alike and the figure alongside represents one of them. The thin strip was then transferred to a drop of strong sugar solution and re-examined under the microscope after about five minutes.
(i) Make a sketch of one of the epidermal cells, as it might appear after immersion in a strong sugar solution. Label any two parts which have undergone a change.
(ii) Give the scientific term for the change shown in Q.(i) above.
(iii) What would you do to bring this cell back to its original condition?
(iv) Give the scientific term used for the recovery of the cell as a result of the step taken in Q.(iii) above.
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Solution
(i) See figure.
(ii) Plasmolysis.
(iii) We would immerse this cell into freshwater, i.e., hypotonic solution.
(iv) Deplasmolysis.
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