Titlebook: Ultrastructure of Reproduction; Gametogenesis, Ferti Jonathan Blerkom,Pietro M. Motta Book 1984 Martinus Nijhoff Publishers, Boston 1984 bi

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Origin of the germ cell lineexamples, PGCs are identified first in the posterior blastoderm in certain insect embryos, in the floor of the blastocoel in anuran frogs, in the anterior extraembryonic endoderm in chicks and in the endoderm of the yolk sac in mammals. It is tempting to make the generalization from these findings t

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conjunctivitis