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The Endowment for Human Development
The Endowment for Human Development
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Slideshow: Early Events

Blastocyst with Inner Cell Mass

#16, Slide 16 of 24

5 days

From The Biology of Prenatal Development.Buy Now

Note:

The inner cell mass is made up of embryonic stem cells.

Label Key:

1. zona pellucida
2. blastocyst cavity
3. inner cell mass
All ages referenced to fertilization, not last menstrual period.
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