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amnion, amniotic cavity, cytotrophoblast, embryonic disc, embryonic endoderm, endometrial stroma, epiblast, extra-embryonic coelom, extra-embryonic endoblast, extra-embryonic mesoblast, fibrous coagulum, intercommunicating lacunae, maternal blood cells in trophoblast lacuna, primary villus, primary yolk sac cavity (exocoelom), syncytiotrophoblast, uterine cavity

The 12-day embryo with primary villi (late bilaminar blastocyst)
Stage 5
Age 12 days
Carnegie collection 7700

Hertig and Rock, 1941.


Keywords: amnion, amniotic cavity, cytotrophoblast, embryonic disc, embryonic endoderm, endometrial stroma, epiblast, extra-embryonic coelom, extra-embryonic endoblast, extra-embryonic mesoblast, fibrous coagulum, intercommunicating lacunae, maternal blood cells in trophoblast lacuna, primary villus, primary yolk sac cavity (exocoelom), syncytiotrophoblast, uterine cavity

Source: Atlas of Human Embryos.