Summary
Kinocilia of epidermal sensory cells in fixed marine Turbellaria often terminate as flattened biconcave discs. The distal part of the ciliary axoneme curves back upon itself forming a 360° loop which is enveloped by the plasmalemma. In living animals this structure can be induced by the addition of sodium cacodylate, monobasic sodium phosphate, dibasic sodium phosphate, sucrose, calcium chloride, or formaldehyde to the sea water. Specimens treated with sodium chloride, glutaraldehyde, or osmium tetroxide do not show modified cilia. In animals prepared for EM at low temperature and with a buffered hypotonic fixative less kinocilia are modified than in animals treated with a buffered iso- or hypertonic fixative and at a higher temperature. It is assumed that the unusually shaped cilia, described as “paddle cilia” or “discocilia” in other invertebrates, do not represent a genuine but an artificial structure.
Similar content being viewed by others
References
Ax, P.: Monographie der Otoplanidae (Turbellaria). Morphologie und Systematik. Akad. Wiss. Lit. Mainz, Abhandl. Math.-naturw. Kl. 1955, Nr. 13, 499–796 (1956)
Baldetorp, L., Mecklenburg, C.v., Håkansson, C.H.: Ultrastructural alterations in ciliary cells exposed to ionizing radiation. A scanning and transmission electron microscopic study. Cell Tiss. Res. 180, 421–431 (1977)
Barber, V.C., Wright, D.E.: The fine structure of the sense organs of the cephalopod mollusc Nautilus. Z. Zellforsch. 102, 293–312 (1969)
Bedini, C., Ferrero, E., Lanfranchi, A.: Fine structural observations on the ciliary receptors in the epidermis of three otoplanid species (Turbellaria, Proseriata). Tissue & Cell 7, 253–266 (1975)
Bergquist, P.R., Green, C.R., Sinclair, M.E., Roberts, H.S.: The morphology of cilia in sponge larvae. Tissue & Cell 9, 179–184 (1977)
Cobb, J.L.S.: Modified cilia in the gut of the lamellibranch mollusc Tapes watlingi. J. Cell Biol. 43, 192–195 (1969)
Dilly, P.N.: Material transport within specialised ciliary shafts on Rhabdopleura zooids. Cell Tiss. Res. 180, 367–381 (1977a)
Dilly, P.N.: Further observations of transport within paddle cilia. Cell Tiss. Res. 185, 105–113 (1977b)
Ehlers, U., Ehlers, B.: Monociliary receptors in interstitial Proseriata and Neorhabdocoela (Turbellaria Neoophora). Zoomorphologie 86, 197–222 (1977)
Heimler, W.: Discocilia ⊕ new type of kinocilia in the larvae of Lanice conchilega (Polychaeta, Terebellomorpha). Cell Tiss. Res. 187, 271–280 (1978)
Kharkeevich, T.A.: Electron microscope study on the statocyst in Arenicola marina under acceleration, vibration and sound influence. Tsitologiya SSSR 19, 120–122 (1977)
Kilburn, K.H., Hess, R.A., Thurston, R.J., Smith, T.J.: Ultrastructural features of osmotic shock in mussel gill cilia. J. Ultrastruct. Res. 60, 34–43 (1977)
Lane, D.J.W., Nott, J.A.: A study of the morphology, fine structure and histochemistry of the foot of the pediveliger of Mytilus edulis L. J. mar. biol. Ass. U. K. 55, 477–495 (1975)
Luther, A.: Zur Kenntnis der Gattung Macrostoma. In: Festschrift für Prof. Palmén, Vol. 1, part 5, pp. 1–61. Helsingfors 1905
Mecklenburg, C.v., Mercke, U., Håkansson, C.H., Toremalm, N.G.: Morphological changes in ciliary cells due to heat exposure. A scanning electron microscopic study. Cell Tiss. Res. 148, 45–56 (1974)
Moir, A.J.G.: On the ultrastructure of the abdominal sense organ of the giant scallop, Placopecten magellanicus (Gmelin). Cell Tiss. Res. 184, 359–366 (1977)
Oldfield, S.C.: Surface fine structure of the globiferous pedicellariae of the regular echinoid, Psammechinus miliaris Gmelin. Cell Tiss. Res. 162, 377–385 (1975)
Reese, T.S.: Olfactory cilia in the frog. J. Cell Biol. 25, 209–230 (1965)
Seifert, K.: Die Ultrastruktur des Riechepithels beim Makrosmatiker. Eine elektronenmikroskopische Untersuchung. In: Normale und Pathologische Anatomie, Vol. 21 (W. Bargmann, V. Doerr, eds.), pp. 1–99. Stuttgart: G. Thieme 1970
Storch, V.: Elektronenmikroskopische und histochemische Untersuchungen über Rezeptoren von Gastropoden (Prosobranchia, Opisthobranchia). Z. wiss. Zool. 184, 1–26 (1972)
Storch, V., Alberti, G.: Ultrastructural observations on the gills of polychaetes. Helgoländer wiss. Meeresunters. 31, 169–179 (1978)
Storch, V., Moritz, K.: Zur Feinstruktur der Sinnesorgane von Lineus ruber O.F. Müller (Nemertini, Heteronemertini). Z. Zellforsch. 117, 212–225 (1971)
Storch, V., Welsch, U.: Über Bau und Funktion der Nudibranchier-Rhinophoren. Z. Zellforsch. 97, 528–536 (1969)
Tamarin, A., Lewis, P., Askey, J.: Specialized cilia of the byssus attachment plaque forming region in Mytilus californianus. J. Morph. 142, 321–327 (1974)
Tamarin, A., Lewis, P., Askey, J.: The structure and formation of the byssus attachment plaque in Mytilus. J. Morph. 149, 199–221 (1976)
Welsch, U., Storch, V.: Über das Osphradium der prosobranchen Schnecken Buccinum undatum L. und Neptunea antigua (L). Z. Zellforsch. 95, 317–330 (1969)
Author information
Authors and Affiliations
Additional information
Thanks are due to Dr. C. Marschall for correcting the English of the manuscript. Financial support was provided by the Akademie der Wissenschaften und der Literatur, Mainz
Rights and permissions
About this article
Cite this article
Ehlers, U., Ehlers, B. Paddle cilia and discocilia — Genuine structures?. Cell Tissue Res. 192, 489–501 (1978). https://doi.org/10.1007/BF00212328
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00212328