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The Endowment for Human Development
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Yolk Sac and Vitelline Vessels

5 weeks, 2 days

From The Biology of Prenatal Development.Buy Now

Note:

The yolk sac helps feed the embryo until the placenta is operational. It does NOT contain yolk at any time.

Label Key:

1. yolk sac
2. yolk stalk
3. vitelline vessels
All ages referenced to fertilization, not last menstrual period.
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
Vitelline Vessels and Yolk Sac
Vitelline Vessels and Yolk Sac
The Lower Limbs and Back
The Lower Limbs and Back
Central Nervous System
Central Nervous System
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