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The Endowment for Human Development
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Yolk Sac and Vitelline Vessels

5 weeks, 6 days

From The Biology of Prenatal Development.Buy Now

Note:

According to some experts, the preferred name for "yolk sac" is "umbilical vesicle."

Label Key:

1. vitelline vessels
2. yolk sac
All ages referenced to fertilization, not last menstrual period.
Heart Chambers
Heart Chambers
The Vital Organs
The Vital Organs
Yolk Sac and Vitelline Vessels
Yolk Sac and Vitelline Vessels
Yolk Sac
Yolk Sac
The Beating Heart
The Beating Heart
Hand Plate and Vital Organs
Hand Plate and Vital Organs
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