Question

what happens when a cell is put into hypotonic,hypertonic and isotonic solution?

Answer 1

it shrink and expand

Answer 2

In a hypotonic solution, the concentration of water molecules is higher outside the cell, or the concentration of solute is lower outside the cell. This causes endosmosis of water, and the cell becomes turgid.
In an isotonic solution, the concentration is same both inside and outside the cell. So, the amount of water leaving the cell is equal to the amount of water entering the cell and there is no change.
In a hypertonic solution, the concentration of water molecules is lower outside the cell or the concentration of solute is higher outside the cell. So, exosmosis occurs and the cell becomes flaccid. If it is a plant cell, it gets plasmolysed.