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The Endowment for Human Development
The Endowment for Human Development
Improving lifelong health one pregnancy at a time.
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Left Lateral View: 3-Week Embryo

3 weeks

From The Biology of Prenatal Development.Buy Now

Label Key:

1. amnion
2. cephalic end of the embryo (meaning "toward the head")
3. yolk sac
4. embryo proper
5. amniotic cavity
6. caudal end (meaning "toward the tail")
7. umbilical cord
All ages referenced to fertilization, not last menstrual period.
Tube Shaped Heart
Tube Shaped Heart
Three-Week Embryo
Three-Week Embryo
Left Lateral View: 3-Week Embryo
Left Lateral View: 3-Week Embryo
Three-Week Embryo
Three-Week Embryo
3-Week Embryo
3-Week Embryo
The Folding of the Embryo
The Folding of the Embryo
When does health begin? Find out now.
Buy the Biology of Prenatal Development DVD