Select the correct answer to the questions from the given options. (Do not copy the questions, write the correct answer only.)
Deplasmolysis occurs when a plasmolysed cell is placed in:
Topic: Deplasmolysis
Try it
Pick an option and check your answer. The full worked answer is below either way.
Answer
(b) Tap water.
DEPLASMOLYSIS is the RECOVERY of a plasmolysed cell, so water must move back INTO it. That requires the surrounding solution to be HYPOTONIC — more dilute than the cell sap — and tap water is exactly that.
The other three options are all HYPERTONIC (more concentrated than the cell sap), and each would draw water further OUT, deepening the plasmolysis rather than reversing it. Notice that they are three ways of saying the same thing, which is a hint in itself: when three options are equivalent, the odd one is the answer.
THE RULE: water moves from the more dilute to the more concentrated solution. HYPERTONIC outside — water leaves — plasmolysis HYPOTONIC outside — water enters — deplasmolysis
Note that recovery is only possible if the cell has not been plasmolysed too long; a cell left in a strong solution eventually dies.
Tap water.