Study of Osmosis


Important Vocabulary Words to Know for this Experiment

Note the root words which will help you to understand these words and to learn new words fast!


Flaccid – soft, limp, without firmness. In biology, flaccid indicates the state of cells where the structure is weakened due to lack of fluid within the cell.

Hypertonic – 1. a solution with higher osmotic pressure.  2. excessive muscle tension. (Hyper = over, above, e.g. hyperactive, hyperglycaemia).

Hypotonic – 1. a solution with a lower osmotic pressure than a comparison solution. 2. abnormally low muscle tension. (Hypo = under, low, e.g. hypothermia).

Isotonic – two solutions with equal osmotic pressure or muscles with equal tension.  (Iso- = equal, e.g. isomer).

Plamolyzed - past participle of the verb ‘plasmolyse’ (British English) or ‘plasmolyze’ (U.S English) – to cause a cell to undergo plasmolysis. Plasmolysis – the protoplasm of a plant or bacteria cell shrinks and separates from the cell wall due to exosmosis.

Regulate – to control or regulate the speed of something. (Reg- = to rule or direct. Examples; regimen, regent, regal, region).


Semipermeable – describes a material that allows only some substances through. (Semi-  - half or partial. E.g. Semipermeable, semi-automatic, semi-final).

Solvent – a liquid that dissolves other substances.

Toxic – poison.

Turgid – swollen or bloated.