Important vocabulary and terms!

Permeable membrane: a cell membrane that regulates what can come in and out of the cell, so that certain substances can move across the cell membrane while others cannot.

Diffusion: the movement of molecules from a higher to a lower concentration.

Osmosis: the diffusion of water across a differentially permeable membrane due to concentration differences.

Turgor pressure: created from the swelling of a plant cell in a hypotonic solution.

Hypotonic: solutions that cause cells to swell, or even to burst due to an intake of water. Water level inside cell < outside the cell (osmosis occurs, and the cell bursts).

Hypertonic: solutions that cause cells to shrink or shrivel due to loss of water.
Water level inside cell is > outside the cell (osmosis occurs, and the cell shrivels).

Isotonic: the solute and water concentration inside and outside the cell are equal.