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The Endowment for Human Development
The Endowment for Human Development
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Slideshow: Umbilical Cord, Placenta & More

Vitelline Vessels and Yolk Sac

#85, Slide 3 of 35

5 weeks, 2 days

From The Biology of Prenatal Development.Buy Now

Note:

The yolk sac is not enclosed within the amnion.

Label Key:

1. vitelline vessels within yolk stalk
2. yolk sac
All ages referenced to fertilization, not last menstrual period.
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