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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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In a foetus, thyroxine secretion begins by?
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The correct answer is  Thyroxine secretion begins by 10th to 12th weeks. Glucagon secretion begins by 8th week. Insulin containing granules can be identified in the human foetal pancreas by 9 to 10 weeks. and insulin in foetal plasma is detectable at 12 weeks. Ref: Williams Obstetrics, 22/e, Page 108 ; Dutta Obstetrics 6/e, Page 43