Tonicity and Osmolarity

Hypertonic Solution

A solution with a higher solute concentration than the cell. Causes water to leave the cell, leading to cell shrinkage (crenation in animal cells).

Hypotonic Solution

A solution with a lower solute concentration than the cell. Causes water to enter the cell, leading to cell swelling and potential lysis (bursting) in animal cells.

Isotonic Solution

A solution with the same solute concentration as the cell. Results in no net water movement, and the cell volume remains stable.

Hyper-osmotic Solution

A solution with a higher total solute concentration (and lower water concentration) compared to another solution.

Hypo-osmotic Solution

A solution with a lower total solute concentration (and higher water concentration) compared to another solution.

Iso-osmotic Solution

Two solutions that have the same total solute concentration (and same water concentration).