Question

When a cell placed in a distilled water,it swells. What process is involved in it?Define it.

Answer 1

The process involves is osmosis.
Osmosis is transfer of solvent material from higher concentration side to lower concentration side.

Answer 2

If the cell is an animal cell it will burst but if it is plant cell,the water will enter the cell and cell swells. This phenomenon is called osmosis.
Osmosis is the spontaneous net movement of solvent molecules through a selectively permeable membrane into a region of higher solute concentration, in the direction that tends to equalize the solute concentrations on the two sides