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Contact: David Bricker
brickerd@indiana.edu
812-856-9035
Indiana University
Caption: Sea urchins and most other animals begin their embryonic development as small clusters of cells, called blastulas. The blastulas are surrounded by a protective fertilization envelope
Credit: Rudolf and Elizabeth Raff
Usage Restrictions: Must include the credit
Related news release: Embryos tell story of Earth's earliest animals
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