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Note:The inner cell mass gives rise to the epiblast and hypoblast.Label Key:1. amniotic cavity 2. extra-embryonic endoderm 3. amnion ectoderm 4. epiblast 5. hypoblast 6. primary yolk sac (also called the primary umbilical vesicle) | ||
All ages referenced to fertilization, not last menstrual period. |