During embryogenesis, primitive precursors to germ cells migrate from the yolk sac to take up residence in the:
a. Cloaca
b. Mesonephric duct
c. Metanephros
d. Oviducts
e. Urogenital ridges of the mesonephros
ANS: E
Primordial germ cells migrate from the yolk sac to the urogenital ridge, apparently following a chemical attractant called stromal cell factor 1.
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