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Embryology of sea urchin: fertilized egg


remnants of fertilization membrane

English name: Sea urchin
Scientific name: Psammechinus sp.
Familia: Echinidae
Classis: Echinoidea
Phylum: Echinodermata
Regnum: Animalia

The fertilized egg can be recognized from the presence of a fertilization membrane (=fertilization envelope). This membrane arises after penetration of the first sperm cell into the egg and prevents further fertilization by other sperms. The perivitelline space is located between the fertilization membrane and the yolk. (None of thse two structures is clearly visible in this preparation, but remnants of the fertilization membrane are indicated with 1).
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last modified: 5 Jun 2014