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The Endowment for Human Development
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Head and Heart

4 weeks, 6 days

From The Biology of Prenatal Development.Buy Now

Note:

If you look just above the heart, it seems like you can look right through the chest.

Label Key:

1. forebrain
2. 1st pharyngeal arch (maxillary process)
3. mouth (stomodeum)
4. 1st pharyngeal arch (mandibular process)
5. auricular groove
6. 2nd pharyngeal arch
7. 3rd pharyngeal arch
8. chest wall
9. liver
10. heart
11. cervical sinus
All ages referenced to fertilization, not last menstrual period.
Head and Neck
Head and Neck
Upper and Lower Limb Buds
Upper and Lower Limb Buds
Head and Heart
Head and Heart
Upper and Lower Limb Buds
Upper and Lower Limb Buds
The Lower Embryo
The Lower Embryo
Yolk Sac and Vitelline Vessels
Yolk Sac and Vitelline Vessels
Buy the Biology of Prenatal Development DVD
Free resources and training for educators