implantation: Quick Facts

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Three labeled cross-section diagrams show the development of a human embryo implanted in the uterine lining at 7.5, 13, and 23 days, highlighting structures such as the embryonic disk, amniotic cavity, yolk sac, trophoblast, and chorion.

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Topics

delayed implantation embryo sexual differentiation gestational age cleavage segmentation induction histogenesis organogenesis neural crest umbilical cord notochord

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