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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
Primordial germ cells are seen in ------ by 3rd week of development?
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The correct answer is  Primordial germ cells originate in the epiblast, migrate through the primitive streak, and by the third week reside among endoderm cells in the wall of the yolk sac close to the allantois. Germ cells do not appear in the genital ridges until the sixth week of development Ref: Langman's embryology; Chapter 16; Pg no 243