COORDINATION OF COMPOUND ASCIDIANS BY EPITHELIAL CONDUCTION IN THE COLONIAL BLOOD VESSELSt
نویسنده
چکیده
Bursts of electrical potentials propagate at ca. 2.0 cm s' within the colonial vascularsystem ofBotryllus, Botryioides, and Metandrocarpa, servingto coordinate contractions of the vascular ampullae and mediating protective closure and ciliary arrest in zooids. Nerves are absent from the vessels and ampullae. Impulses are presumed to propagate from cell to cell in the vascular epithelium via gap junctions, shown to be present by electron microscopy.
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