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The Endowment for Human Development
The Endowment for Human Development
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Two-Cell Human Embryo

36 hours

From The Biology of Prenatal Development.Buy Now

Note:

Each cell in the early embryo is called a blastomere.

Label Key:

1. perivitelline space
2. outline of blastomere #1
3. zona pellucida
4. cell membrane of blastomere #2
All ages referenced to fertilization, not last menstrual period.
Human Zygote
Human Zygote
The Zygote
The Zygote
Two-Cell Human Embryo
Two-Cell Human Embryo
Two-Cell Embryo
Two-Cell Embryo
Three-Cell Embryo
Three-Cell Embryo
Four-Cell Human Embryo
Four-Cell Human Embryo
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