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Distribution of Sodium, Potassium and Chloride in the Ophiuroid, Ophiocomina Nigra (Abildgaard)

Published online by Cambridge University Press:  11 May 2009

Richard M. Pagett
Affiliation:
Department of Earth Sciences, The University, Leeds

Extract

Echinoderms are not generally considered to experience significant dilution of the surrounding medium in their usual marine habitats and so it is to be expected that, due to the absence of any obvious excretory organ, the ionic composition of the body fluid would be similar to that of the ambient sea water. In general this has been confirmed by previous workers for many species of echinoderm. Binyon (1966) lists the results of workers who have determined osmotic pressure and/or ionic concentrations in the perivisceral and/or ambulacral fluids of many echinoderms. With reference to the perivisceral fluid in asteroids there is usually a small excess of potassium (9–16%) which is maintained in the more euryhaline species and in those acclimatized to reduced salinity. Generally, the chloride content is similar to, or a little higher than, that in the surrounding sea water. In echinoids there is little difference in the potassium content and chloride concentrations with respect to sea water though there may be a small increase in the former ion. In the holothurians, there is little regulation of potassium ions. Such concentrations which have been determined for the chloride ion in this group are found to be a little higher than in sea water. The sodium concentration in the perivisceral fluids of echinoderms tends to be similar to, or slightly lower than, that in the surrounding sea water. However in the ambulacral fluids of the water vascular system it has been shown that the potassium concentration is 20–90% higher in some species of asteroids and echinoids (Robertson, 1949; Binyon, 1962,1966). The fluids of the water vascular system of echinoderms, analysed to date, have concentrations of sodium ions lower than in the ambient sea water. From the available evidence, there appears to be little difference between environmental and ambulacral chloride concentrations.

Type
Research Article
Copyright
Copyright © Marine Biological Association of the United Kingdom 1980

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References

Bethe, A. & Berger, E., 1931. Variationen im Mineralbestand verschiedener Blutarten. Pflügers Archiv für die gesamte Physiologie des Menschen und der Tiere, 227, 571584.Google Scholar
Bialaszewicz, K., 1933. Contribution à l'étude de la composition minérale des liquides nourriciers chez les animaux marins. Archives internationales de physiologie, 36, 4153.Google Scholar
Binyon, J., 1962. Ionic regulation and mode of adjustment to reduced salinity of the starfish, Asterias rubens. Journal of the Marine Biological Association of the United Kingdom, 42, 4964.Google Scholar
Binyon, J., 1966. Salinity tolerance and ionic regulation. In Physiology of Echinodermata (ed. Boolootian, R. A.), pp. 359377. New York: Interscience.Google Scholar
Cole, W. H., 1940. The composition of fluids and sera of some marine animals and of the sea water in which they live. Journal of General Physiology, 23, 575584.CrossRefGoogle ScholarPubMed
Conway, E. J., 1957. Microdiffusion Analysis and Associated Volumetric Errors, 4th edition. 465 pp. London: Crosby and Lockwood.Google Scholar
Gurr, G. T., 1963. Biological Staining Methods, 7th edition. London: George T. Gurr Ltd.Google Scholar
Koizumi, T., 1935. Studies on the exchange and the equilibrium of water and electrolytes in a holothurian, Caudina chilensis (J. Müller). II. On the velocity of permeation of Cl′ and SO4″ through the isolated body wall of Caudina. Science Reports. Tohoku Imperial University (ser. 4), Biology, 10, 269275.Google Scholar
Myers, R. G., 1920. A chemical study of several invertebrate animals. Journal of Biological Chemistry, 41, 119135.Google Scholar
Parker, B. & Cole, W. H., 1940. Studies of the body fluids and sera of some marine invertebrates. Bulletin. Mount Desert Island Biological Laboratory, 1940, 3638.Google Scholar
Robertson, J. D., 1949. Ionic regulation in some invertebrates. Journal of Experimental Biology, 26, 182200.Google Scholar
Robertson, J. D., 1953. Further studies on ionic regulation in marine invertebrates. Journal of Experimental Biology, 30, 277296.Google Scholar
Schlieper, C., 1957. Comparative study of Asterias rubens and Mytilus edulis from the North Sea and the Western Baltic. Annals of Applied Biology, 33, 117127.Google Scholar
Stickle, W. B. & Ahokas, R., 1974. The effects of tidal fluctuation of salinity on the perivisceral fluid composition of several echinoderms. Comparative Biochemistry and Physiology, 47A, 469476.CrossRefGoogle Scholar
Woodley, J. D., 1967. Problems in the ophiuroid water vascular system. Symposia of the Zoological Society of London, no. 20, 75104.Google Scholar