4 weeks: Embryo floats in amniotic sac, connected to uterus wall only by umbilical cord. Embryo has large head, gills, tail, somites on notochord sides, and beating heart {head and heart development}.
Biological Sciences>Zoology>Development>Stages>Gestation>Embryo 028 Day
4-Zoology-Development-Stages-Gestation-Embryo 028 Day
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Date Modified: 2022.0224