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The Endowment for Human Development
The Endowment for Human Development
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The Yolk Sac


5 weeks, 2 days

From The Biology of Prenatal Development.Buy Now

Script: The yolk sac contains early reproductive cells called germ cells. By 5 weeks these germ cells migrate to the reproductive organs adjacent to the kidneys.

All ages referenced to fertilization, not last menstrual period.
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Transparent Skin
Transparent Skin
Cerebral Hemispheres
Cerebral Hemispheres
The Yolk Sac
The Yolk Sac
The Liver and Heart
The Liver and Heart
Hand Plates and Cartilage
Hand Plates and Cartilage
Brainwaves
Brainwaves
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