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Summary Stage Literature (90) Attributions Wiki

Name: 1-cell stage

ECAO ID: 0000140

Definition: "A fertilized egg, right after fertilization. The embryo is characterized morphologically by the fact that it is a single diploid cell surrounded by a fertilization envelope. This stage corresponds to an embryo of age 0 hour post-fertilization."

Preceded By: mature spermatozoid stage Succeeded By: 2-cell stage