Chapter 111 - Part B: Heat Kills Output: Why Testicles Live Outside the Body

About this episode

This episode discusses the role of temperature in male reproductive anatomy and its impact on fertility.

In this BoardsCast episode, we continue Tobias Chapter 111 — Testes, Epididymides, and Scrotum by reframing male reproductive anatomy with the only rule that actually predicts outcomes: Temperature dictates spermatogenesis — and spermatogenesis dictates fertility. The scrotum isn’t a “pouch.” It’s an actively engineered temperature control system that keeps the seminiferous tubules 2–3°C below core temperature—because at core temperature, the sperm factory shuts down. We break down the ...

Topics covered

• male reproductive anatomy
• spermatogenesis
• fertility
• temperature control
• scrotum function

Keywords

• testicles
• epididymides
• scrotum
• spermatogenesis
• fertility
• temperature regulation

Mentioned in this episode

Books & works: Tobias Chapter 111

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