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The Endowment for Human Development
The Endowment for Human Development
Improving lifelong health one pregnancy at a time.
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Secondary Oocyte

Secondary Oocyte [Click for next image]
Source: Centro Riproduzione Assistita, Catania, Italy.

Label Key:

1. zona pellucida
2. polar body
3. secondary oocyte
4. perivitelline space
All ages referenced to fertilization, not last menstrual period.
Chromosomes and the Nucleus
Chromosomes and the Nucleus
Sperm
Sperm
Secondary Oocyte
Secondary Oocyte
Single-Cell Embryo
Single-Cell Embryo
Zygote
Zygote
Human Zygote
Human Zygote
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