The movement of water in and out of a cell is called osmosis.

Here's a breakdown:

* Osmosis is the passive movement of water molecules across a semipermeable membrane from an area of high water concentration to an area of low water concentration. This movement is driven by the difference in water potential between the two areas.

* Semipermeable membrane is a membrane that allows some molecules to pass through but not others. In the case of cells, the cell membrane acts as a semipermeable membrane.

* Water potential is the potential energy of water in a particular environment, and it is influenced by factors like solute concentration and pressure.

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