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The Endowment for Human Development
The Endowment for Human Development
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Sperm

Source: Centro Riproduzione Assistita, Catania, Italy.

Label Key:

1. spermatozoa
All ages referenced to fertilization, not last menstrual period.
A Human Cell
A Human Cell
Chromosomes and the Nucleus
Chromosomes and the Nucleus
Sperm
Sperm
Secondary Oocyte
Secondary Oocyte
Single-Cell Embryo
Single-Cell Embryo
Zygote
Zygote
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