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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
Testosterone production is mainly contributed by:
assistant
The correct answer is  Testosterone is a Cl 9 steroid that is synthesized from cholesterol within the interstitial Leydig cells. Ref: Ganong's Review of Medical Physiology, 22nd Edition, Pages 424-25; Good Clinical Practice in Assisted Reproduction By Paul Serhal, Caroline Oveon, 2004, Page 25.