IB Biology Topic D2.3: Water Potential Key Definitions

A solution with a higher solute concentration compared to another solution.

A solution with a lower solute concentration compared to another solution.

Two solutions with equal solute concentrations, resulting in no net movement of water.

Osmosis is the net movement of water molecules across a semi-permeable membrane from a region of lower solute concentration to a region of higher solute concentration.

Osmosis is the passive movement of water molecules across a semi-permeable membrane from a region of lower solute concentration (hypotonic) to a region of higher solute concentration (hypertonic).

Plasmolysis is the process where the cell membrane pulls away from the cell wall due to water loss.

Pressure potential ($\psi_p$) reflects the physical pressure exerted on water.

Solute concentration refers to the amount of solute (a substance dissolved) present in a given quantity of solvent (a liquid in which the solute is dissolved) or solution.

Solute potential ($\psi_s$) measures how solutes affect water's potential energy.

Solvation is the process where solvent molecules surround and interact with solute particles, stabilizing them in solution.

Turgid refers to a plant cell that is swollen with water, causing the cell membrane to press tightly against the cell wall.

Turgor pressure is the pressure exerted by the cell contents against the cell wall.

Water potential ($\Psi$) is a measure of the potential energy of water per unit volume, determining the direction water will move.