gastrula

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Poker game. Card game. Royal Flush in poker. Hearts suit gambling

Poker Hands Ranked

Periodical Cicada, Adult, Magicicada spp. Requires 17 years to complete development. Nymph splits its skin, and transforms into an adult. Feeds on sap of tree roots. Northern Illinois Brood. This brood is the largest emergence of cicadas anywhere

Why Do Some Cicadas Appear Only Every 17 Years?

Aurochs. Bos primigenius. Skeleton. Extinct animal. Skeleton of an Aurochs, an extinct wild ox.

6 Animals We Ate Into Extinction

Ethel Rosenberg arrested in August 1950. Photograph dated Aug. 8, 1950. American civilians executed for espionage. Spies, communists, Julius Rosenberg

Spies Like Us: 10 Famous Names in the Espionage Game

Drinking water is poured into a glass.

Water Fluoridation: Just the Facts

Close up of books. Stack of books, pile of books, literature, reading. Homepage 2010, arts and entertainment, history and society

12 Novels Considered the “Greatest Book Ever Written”

Happy, smiling, flying pig

7 Everyday English Idioms and Where They Come From

gastrula: Related Content

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Topics

primitive streak germ layer archenteron epiblast blastopore diploblastic cell system triploblastic cell system endoderm ectoderm mesoderm

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animal development: Embryo formation