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Slideshow: The Developing Brain

Four-Week Embryo

#35, Slide 3 of 21

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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