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  • 1
    Publication Date: 1977-02-01
    Print ISSN: 0302-766X
    Electronic ISSN: 1432-0878
    Topics: Biology , Medicine
    Published by Springer
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  • 2
  • 3
    ISSN: 1432-234X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Zusammenfassung Die Ultrastruktur des Genitaltraktes vonPeripatopsis moseleyi wird beschrieben. Im Hoden finden sich neben somalischen Zellen Spermatogonien und Spermatocyten. In letzteren werden in gro\er Zahl Sekreteinschlüsse gebildet, die spÄter zusammenflie\en und abgegeben werden; sie sind noch in der Spermatophore nachweisbar. Die Spermiocytogenese lÄuft in den Vesiculae seminales ab. Kernkondensation und -Umformung, Mittelstückformation und Akrosombildung werden beschrieben. Das reife Spermium hat einen langgestreckten Kern, ein Mittelstück, das nur aus Mitochondrien besteht, und einen Schwanz mit verschiedenen Mikrotubulus-Formationen. Die Spermatophorenbildung geht mit intensiver Sekretion der Epithelzellen des Vas deferens einher.
    Notes: Summary The ultrastructure of the male genital tract ofPeripatopsis moseleyi has been examined under the electron microscope. In the testes somatic cells, spermatogonia and spermatocytes occur. In the spermatocytes electron-dense granules are built by the Golgi-apparatus. They are released from the developing spermatid and can still be detected in the spermatophore. The spermiogenesis takes place in the seminal vesicles. Nuclear condensation and elongation, formation of middle piece and acrosome are described. The mature sperm cell has an elongated nucleus, a middle piece containing mitochondria only and a tail with 9+2-formation and accessory microtubule systems. The spermatophore is built within the vas deferens the epithelial cells of which secrete great amounts of material enveloping the sperm mass.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Springer
    Zoomorphology 87 (1977), S. 263-276 
    ISSN: 1432-234X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Zusammenfassung Alle Teile des männlichen Genitaltraktes vonOpisthopatus cinctipes sind an der Entstehung der Spermatophore beteiligt. In den Spermatocyten der Hoden werden in großer Zahl elektronendichte Sekreteinschlüsse produziert, die in den Vesiculae seminales zusammenfließen und aus der Spermatide in das Vesicula-Lumen entlassen werden. Während der Spermiocytogenese wird ein zweiter Typ von Einschlußkörpern gebildet, den wir als Akrosom-Vesikel deuten; auch er wird in der Samenblase ausgeschleust. In der Passage durch die Vasa efferentia werden fast reife Spermien und Sekret voneinander getrennt. An der Peripherie liegen die Sekrete, im Zentrum die Spermien. Im Vas deferens werden die Samenpakete von einer mehrschichtigen Sekrethülle umgeben. Durch den muskulösen Ductus ejaculatorius wird die Spermatophore abgegeben, auch in ihm finden sich Drüsenzellen. Dem Transport dienen in Vasa efferentia und Vas deferens Cilien.
    Notes: Summary All parts of the male genital tract ofOpisthopatus cinctipes are involved with the formation of the Spermatophore. In the spermatocytes within the testes a Golgi apparatus produces electron dense secretory granules merging into one large droplet, which is extruded by the spermatid within the seminal vesicle. A second vesicular structure is formed near the plasmamembrane of the spermatids by a Golgi apparatus. It is presumably an acrosome vesicle and is extruded into the seminal vesicle, too. During the passage through the vasa efferentia secretory products and sperm-cells are separated from each other, the secretory products building an envelope around the spermatozoa. The epithelium of the vas deferens adds a multilayered outer covering. Some parts of the male genital tract bear cilia (vasa efferentia, vas deferens).
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  • 5
    Electronic Resource
    Electronic Resource
    Springer
    Cell & tissue research 177 (1977), S. 539-553 
    ISSN: 1432-0878
    Keywords: Sensory receptors ; Peripatopsis ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Three types of sensilla occurring on the lips and on the antennae of Peripatopsis moseleyi have been investigated by scanning and transmission electron microscopy. On the lips sensory spines can be found which contain numerous cilia originating from bipolar receptor cells. They reach the tip of the spine where the cuticle is modified. The perikarya of the sensory cells, a large supporting cell with a complicated surface and a second type of receptor, form a bud-like structure and are surrounded by a layer of collagen fibrils. The second receptor cell bears apical stereocilia as well as a kinocilium which are directed towards the centre of the animal — thus the cell appears to be turned upside down. The sensilla of the antennae are 1) sensory bristles containing two or three kinds of receptor cells, one of which bears an apical cilium and one kind of supportive cell and 2) sensory bulbs located within furrows consisting of receptor cells with branched cilia and two kinds of supportive cells which are covered by a modified thin cuticle. According to the electron microscopical findings the sensory spines on the lips are presumably chemoreceptors. The sensory bristles on the antennae can be regarded as mechanoreceptors and the sensory bulbs as chemoreceptors.
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  • 6
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Biologie in unserer Zeit 18 (1988), S. 168-173 
    ISSN: 0045-205X
    Keywords: Life and Medical Sciences
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
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