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The Endowment for Human Development
The Endowment for Human Development
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Slideshow: The Developing Brain

The Folding of the Embryo

#34, Slide 1 of 21

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.
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