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Slideshow: Slideshow 1

Vitelline Vessels and Yolk Sac

#85, Slide 7 of 19

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.
Fertilization BeginsThree-Cell EmbryoEarly BlastocystImplantation Well UnderwayThe 4-Week EmbryoVitelline Vessels and Yolk SacHand Plate and Vital OrgansHand, 7 Weeks Pregnant7½-Week EmbryoRight Eye and Facial Profile9-Week Fetus, MRI AnimationExit Stage LeftPosterior Surface of Left ThighStill HidingThe MouthFace, 27-Week FetusFace and Left ForearmReady for Birth and Beyond
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