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Embryonalentwicklung von Branchiostoma lanceolatum (Acrania)

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Formal Metadata

Title Embryonalentwicklung von Branchiostoma lanceolatum (Acrania)
Alternative Title Embryonic Development of Brachiostoma lanceolatum (Acrania)
Author Roschmann, Günter
License No Open Access License:
German copyright law applies. This film may be used for your own use but it may not be distributed via the internet or passed on to external parties.
DOI 10.3203/IWF/C-1166
IWF Signature C 1166
Publisher IWF (Göttingen)
Release Date 1975
Language German
Producer IWF
Production Year 1974

Technical Metadata

IWF Technical Data Film, 16 mm, LT, 109 m ; SW, 10 min

Content Metadata

Subject Area Life Sciences
Abstract Lanzettfischchen. Habitus, Gonaden. Ausstoßen der Geschlechtsprodukte, Spermien, Befruchtung, Befruchtungsmembran, inäquale Furchung, Blastula, Gastrulation (Invagination), Bewegung des Embryos in der Eihülle, Streckung des Keims, Schlüpfvorgang, Schwimmen des Embryos, Entwicklungsstadien an festgelegten Tieren (Organogenese), Fortbewegung der Larve.
This film provides scenes of the embryonic development of the Branchiostoma lanceolatum. Initial scenes show the habitus and gonades of adults. Females are clearly distinguishable from males due to the large number of eggs in the ovaries under the binocular. These scenes are followed by those of sperms, which are among the smallest in the species of the chordates. When a sperm manages to penetrate an egg, this lifts away from the insemination membrane, which forms a transparent protective sheath through the intake of water. A fertilized and an unfertilized egg are shown. Approximatel one hour after fertilization the weak inequal furrowing commences. After gastrulation takes place the embryo starts moving inside the egg sac, since each ectoderm cell has a cilium. Depeding on size and dimension of the embryo various movements take place: turning through the body's cross axis, rotation through the body's long axis. If 2 or 3 primary segements have formed the embryo bursts the egg sac. Emergence and subsequent swimming are shown at normal speeds. In closing single phases of further embryonic development are shown in certain animals. After approximately 48 hours embryonic development is completed. Thy young larvae, in which chorda, mouth opening and the 1st gill opening are now formed, reach the ocean bed by means of varying snakelike movements or simple gliding, once here they commence a complicated process of metamorphosis.
Keywords Lanzettfischchen
Meduse
Branchiostoma lanceolatum
Fortbewegung / Acrania
Embryonalentwicklung / Acrania
Gastrulation
Schlüpfen / Acrania
Larven / Acrania
Furchung / Acrania
embryonic development / Acrania
locomotion / Acrania
gastrulation
larvae / Acrania
hatching / Acrania
cleavage / Acrania
Branchiostoma lanceolatum
lancelet
medusa

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  225 ms - page object

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AV-Portal 3.8.0 (dec2fe8b0ce2e718d55d6f23ab68f0b2424a1f3f)