Control of mouth opening and pharynx protrusion during feeding in the sea anemone Calliactis parasitica.
نویسنده
چکیده
1. Activity in all three known conducting systems (the nerve net, SS1, and SS2) may accompany feeding in Calliactis. The most marked response is an increase in pulse frequency in the SS2 (the endodermal slow conducting system) during mouth opening and pharynx protrusion. 2. Electrical stimulation of the SS2 at a frequency of one shock every 5 s elicits mouth opening and pharynx protrusion in the absence of food. 3. A rise in SS2 pulse frequency is also evoked by food extracts, some amino acids, and in particular by the tripeptide reduced glutathione, which produces a response at a concentration of 10(-5) M. 4. Although the SS2 is an endodermal system, the receptors involved in the response to food appear to be ectodermal. 5. The epithelium that lines the pharynx conducts SS1 pulses, but there is some evidence for polarization of conduction.
منابع مشابه
Title MULTIPLE CONDUCTION SYSTEMS AND THE BEHAVIOUR OF SEA ANEMONES Author(s) Mcfarlane, I. D. Citation PUBLICATIONS OF THE SETO MARINE BIOLOGICAL
Electrical activity can be recorded from three distinct conduction systems-the through-conducting nerve net and two slow systems (SSl and SS2). Spontaneous and evoked pulses are shown in recordings from M etridium senile. The responses and interactions of these systems seem to control important components of actinian behaviour. SSI pulses are seen during the opening of Tealiafe!ina in response ...
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ورودعنوان ژورنال:
- The Journal of experimental biology
دوره 63 3 شماره
صفحات -
تاریخ انتشار 1975