QUICK SEARCH:   [advanced] Author: Keyword(s):
Home     Help     Feedback     Subscriptions     Archive     Search     Table of Contents

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by JONES, W. C. Articles by NESBITT, S. P. Search for Related Content PubMed Articles by JONES, W. C. Articles by NESBITT, S. P.

Journal of Experimental Biology 68,187-198 (1977)
Published by Company of Biologists 1977

A Respiratory Rhythm in Sea Anemones

W. C. JONES ¹, VERONICA J. PICKTHALL ¹, and S. P. NESBITT ¹

¹ Department of Zoology, University College of North Wales, Bangor, Gwynedd LL57 2UW, U.K.

Continuous recording of the O₂ content of sea water containing an Actinia equina or a Metridium senile has revealed the occurrence of periodic deflexions on most of the records obtained. The deflexions are probably caused by the release of coelenteric fluid via the mouth. The average period of the rhythm varied from 24 to 43 min (14–15 °C). The period increased in darkness, but was unaffected by feeding, brief mechanical or electrical stimulation, longitudinal bisection of the column and excess KCl or MgCl₂; 1.6 mMKCN abolished the rhythm. The O₂ depletion rate did not increase when the anemone contracted in response to stimulation, but it did after feeding, exposure to darkness, or the application of MgCl₂. It decreased in the presence of excess KCl. These changes may result from alterations in shape of the anemone. The mechanism for the release of coelenteric fluid has yet to be elucidated. Calculations indicate that from to 1/9 of the total O₂ requirement may enter the tissues from the coelenteron, the remainder being taken up via the ectoderm.