1 blastomere (1 out of 2 daughter cells) 2 blastomere (other out of 2 daughter cells) 3 fertilization membrane 4 first cleavage plane
English name: Sea urchin Scientific name: Psammechinus sp. Familia: Echinidae Classis: Echinoidea Phylum: Echinodermata Regnum: Animalia
Due to the equal divison of yolk over the two blastomeres, the fertilized egg undergoes a complete cleavage: holoblastic cleavage (holo = complete; blasto = germ). To next stage. One stage back.
