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Slideshow: Umbilical Cord, Placenta & More

Yolk Sac and Vitelline Vessels

#82, Slide 7 of 35

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.
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