Yolk Sac

#83, Slide 43 of 58

5 weeks, 6 days

From The Biology of Prenatal Development.

Buy Now

Note:

The yolk sac contains no yolk. However, early in pregnancy the yolk sac absorbs nutrients from the surrounding fluid (provided by the mother) and delivers them to the embryo. Thanks mom!

Label Key:

1. yolk sac

2. vitelline vessels

All ages referenced to fertilization, not last menstrual period.

Tell your story. Create your own pregnancy calendar.

Buy the Biology of Prenatal Development DVD