(1) Osmotic lysis, i.e. the bursting or rupturing of cell membrane when the cell can no longer contain the excessive inflow of water (or extracellular fluid).
(2) The degeneration or dissolution of cell caused by the disruption of cell membrane.
Cytolysis or osmotic lysis occurs in animal cells and certain bacteria, especially when the cells are exposed to a hypotonic environment, causing the water to move into the cell, thereby increasing or expanding the cell. If the cell membrane cannot regulate or hold the excessive influx of water, the cell will eventually burst. Osmotic lysis does not occur in plant cells because of the cell wall that contains the turgor pressure.
Word origin: Greek kutos, hollow vessel + New Latin, from Greek lusis, a loosening.
Related forms: cytolytic (adjective).
Related terms: immune cytolysis.
Synonym: osmotic lysis (1).
See also: osmosis.