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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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Parafollicular cells (C-cells) in the thyroid are derived from
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The correct answer is  Cells of the ultimobranchial body give rise to the parafollicular, or C cells of the thyroid gland. These cells secrete calcitonin, a hormone involved in regulation of the calcium level in the bloodRef: Langman&;s Medical embryology; 12th edition; Chapter 17; Head and Neck