Plasmolysis describes a process involving a plant cell losing water content and therefore contracting and shrinking its cytoplasm and plasma membrane away from its cell wall. This process occurs when a plant cell is surrounded by hypertonic conditions or conditions in which there is a higher concentration of dissolved contents in a solution outside the plant cell than inside. That is, this occurs when the water in a plant and surrounding a plant cell are highly concentrated with dissolved contents. This water which contains dissolved nutrients and exists around and between plant cells is called extracellular fluid. Hypertonic conditions of extracellular fluid rarely occur naturally and can lead to cell death.
Plants do not precisely regulate the extracellular fluid within them. That is, plants do not have control of the water soaking up through their roots and stems, and out of their leaves. This process occurs due to the adhesive and cohesive properties of water. The internal structure of a plant simply acts as a sponge that water can stick to and move up through, which is called capillary action. Automatic and circumstantial processes like this are what govern a plant maintaining homeostasis. Homeostasis is the property of systems (such as a plant) regulating themselves to a relatively stable state or state of equilibrium. A plant is in homeostasis when its internal systems are balanced and contain sufficient water and nutrients.
 |
In biology, lysis refers to the breakdown of a cell caused by damage to its plasma (outer) membrane. It can be caused by chemical or physical means (for example, strong detergents or high-energy sound waves) or by infection with a strain virus that can lyse cells.
"Cell Death." The Gale Encyclopedia of Science, edited by Katherine H. Nemeh and Jacqueline L. Longe, 6th ed., vol. 2, Gale, 2021, p. 870.