Muzvipembenene, blastula larvae inoshambira kuenda kunzvimbo nyowani, inonamatira kune seabed, uye inokura kuita siponji nyowani. Mune mamwe mapoka, blastula inoita shanduko yakaoma kunzwisisa. Inotanga kuvhara kuti igadzire gastrula ine kamuri yekugaya uye maviri akaparadzaniswa germ layers, yekunze ectoderm uye yemukati endoderm. Muzviitiko zvakawanda, yechitatu germ layer, iyo mesoderm, zvakare pakati pavo. Aya majekiseni anogadzira akawanda majekiseni mukati meiyo hollow sphere, inonzi blastula. Muzvipembenene, blastula larvae inoshambira kuenda kunzvimbo nyowani, inonamatira kune seabed, uye inokura kuita siponji nyowani. Mune dzimwe mhuka, izvi zvinowanzoitika nekuda kwekukanganisa kwehukama kwehukama, uko kunokonzerwa nekukwanisa kubereka kuburikidza nehukama hwakawanda.
kubereka kwepabonde