Ion and Water Balance of the Hypo- and Hyperosmotically Stressed Chitonmopalia Muscosa
Year: 1980
Type: article
Abstract: 1. The effects of external salinity changes on whole-animal volume, blood ions, and muscle-tissue water content of the chiton Mopalia muscosa were investigated. The data indicated that short-term low-salinity adaptation in the chiton M. muscosa is achieved by volume control mechanisms that are quickly activated. 2. Blood Na+, Cl-, K+, and Mg2+ were isoionic to the SW concentration in salinities ranging between 60 and 125% SW. Blood Ca2+ concentration was hyper-regulated in hyposmotic SW. 3. Regulation of cell volume occurred in salinity-stressed chitons, as water content of foot-muscle tissue was regulated in both hypo- and hyperosmotic media. 4. When exposed to hyposmotic SW the chitons at first (0-4hr) gained weight; this was followed by a period in which the rate of weight gain approached zero (4-6 hr) and finally by a period of weight loss (6-24hr) (volume regulation). Exposure to hyperosmotic SW resulted in weight loss and little volume regulation. 5. Volume control in hyposmotic media is accomplished, in part, by a loss of solute. 6. Low temperature, 7°C, decreased both the water influx and volume regulation. 7. Volume regulatory mechanisms are activated within 1 hr after exposure to 60% SW.
Source: Biological Bulletin
DOI: 10.2307/1541100
Authors: WILLIAM M. MORAN, RICHARD E. TULLIS
Language: English
Subfield: Ecology
Field: Environmental Science
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W2170683256