Zobrazeno 1 - 10
of 37
pro vyhledávání: '"Norbert Weissenfels"'
Autor:
Norbert Weissenfels
Publikováno v:
Zoomorphology. 111:207-216
A prerequisite for the production of gemmules is the presence of intact archaeocytes and trophocytes, which give rise to the thesocytes with which the gemmule is eventually filled. The coat enclosing the gemmule requires spongioblasts for its formati
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::85b5ef89ce0dfb59c6deb9a4927fd570
https://doi.org/10.1007/bf01633009
https://doi.org/10.1007/bf01633009
Autor:
Norbert Weissenfels
Publikováno v:
Zoomorphology. 112:51-55
The freshwater sponges (Spongillidae) feed by filtering out small particles from the water passing through them by means of strainer devices in the flagellated chambers. These are filamentous, fine-meshed structures at the distal ends of the choanocy
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::1f62d5db548e256b248955e4c9e895f7
https://doi.org/10.1007/bf01632994
https://doi.org/10.1007/bf01632994
Publikováno v:
Cell and Tissue Research. 261:145-154
Different antibodies against actin, tubulin and cytokeratin were utilized to demonstrate the spatial organization of the cytoskeleton in basal epithelial cells of the freshwater sponge Spongilla lacustris. Accordingly, actin is localized in a cortica
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::8eda2c06542e11211b7e8bf549a750e4
https://doi.org/10.1007/bf00329447
https://doi.org/10.1007/bf00329447
Autor:
Norbert Weissenfels
Publikováno v:
Zoomorphology. 98:35-45
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::bd035125c0472ac6265abd2cf6bc9a80
https://doi.org/10.1007/bf00310319
https://doi.org/10.1007/bf00310319
Autor:
Norbert Weissenfels, Wolfgang Paulus
Publikováno v:
Zoomorphology. 106:155-162
Spermatogensis of the freshwater sponge Ephydatia fluviatilis begins with differential mitosis of choanocytes in the flagellated chambers. The spermatogonia thus produced aggregate in the mesenchyme by amoeboid movement. They are surrounded by dendri
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::4b6f04e4c5b84db52b5f7e6ff398633a
https://doi.org/10.1007/bf00312204
https://doi.org/10.1007/bf00312204
Autor:
Norbert Weissenfels, Uwe Saller
Publikováno v:
Zoomorphology. 105:367-374
During June and July oocytes appear in well-developed specimens of Spongilla lacustris. These differentiate from archeocytes, and during the first growth phase they reach a diameter of ca. 50 μm. At this time each oocyte is enclosed in a single-laye
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::690bb103350e2093395169dfc8871641
https://doi.org/10.1007/bf00312280
https://doi.org/10.1007/bf00312280
Autor:
Norbert Weissenfels, Bernd Striegler
Publikováno v:
Zoomorphologie. 92:49-63
Einzelexemplare vonEphydatia fluviatilis konnen fusionieren, sofern diese miteinander vertraglich sind. Wenige Tage alte Jungschwamme verwachsen nach der Kontaktaufnahme vollstandig. Haben die jungen Schwamme ihr ausfuhrendes Kanalsystem vor der Beru
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::a006214b939c6cc630052e3973785d9e
https://doi.org/10.1007/bf00999834
https://doi.org/10.1007/bf00999834
Autor:
Norbert Weissenfels
Publikováno v:
Zoomorphology. 104:292-297
E. f. se contracte rythmiquement, a 15 a 16°C. La frequence de contraction varie entre 4 a 6 heures. L'augmentation de temperature entraine des contractions additionnelles irregulieres
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::ee5bcd5ab3901bc352c91ad5875ce253
https://doi.org/10.1007/bf00312010
https://doi.org/10.1007/bf00312010
Autor:
Norbert Weissenfels
Publikováno v:
Zeitschrift f�r Morphologie der Tiere. 81:241-256
Ephydatia fluviatilis besitzt ein zum einfuhrenden Kanal-system hin “offenes” Mesenchym. Alle Zellen dieses Suswasserschwamms weisen pulsierende Vakuolen auf und fuhren aktive Osmoregulation durch.
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::03ba36cd214876cee97f879c8b8df324
https://doi.org/10.1007/bf00278372
https://doi.org/10.1007/bf00278372