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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.
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The first indication of gastrulation in the embryo is
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The correct answer is  The formation of the primitive streak on the dorsal surface of the bilaminar embryonic disk formed from proliferation at the end of 2nd week (day 14) is the first indication of gastrulation.