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The Endowment for Human Development
The Endowment for Human Development
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The Folding of the Embryo

3 weeks, 3 days

From The Biology of Prenatal Development.Buy Now

Label Key:

1. base of umbilical cord
2. hindbrain
3. midbrain
4. forebrain
5. site of the future opening of the mouth (called the stomodeum)
6. heart
7. yolk sac
All ages referenced to fertilization, not last menstrual period.
Three-Week Embryo
Three-Week Embryo
3-Week Embryo
3-Week Embryo
The Folding of the Embryo
The Folding of the Embryo
The 4-Week Embryo
The 4-Week Embryo
The Folding Heart
The Folding Heart
Four-Week Embryo
Four-Week Embryo
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