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What is Primordial germ cell is derived from and explain in detail?
Primordial germ cell is derived from epiblast, earlier they were believed to arise from endoderm of yolk sac They became evident at the distal end of primitive streak by the 2nd week of intrauterine life, these cells migratory and reach the endodermal wall of yolk sac, they reach the gonad by the 5th week Gray's 39e/p-210-220