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The Endowment for Human Development
The Endowment for Human Development
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Slideshow: Entire Image Gallery by EHD

Four-Week Embryo

#35, Slide 54 of 312

4 weeks

From The Biology of Prenatal Development.Buy Now

Label Key:

1. hindbrain
2. spinal cord
3. foregut
4. heart
5. midgut
6. midbrain
7. forebrain
8. site of future mouth (stomodeum)
9. chest wall
10. yolk sac
11. hindgut
All ages referenced to fertilization, not last menstrual period.
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