Which muscle helps to move the testes in response to heat?

The cremaster muscle plays a crucial role in regulating the position of the testes in response to temperature changes. It is a thin muscle that surrounds the testes and is an extension of the internal oblique muscle. When exposed to heat, the cremaster muscle relaxes, allowing the testes to descend away from the body, which helps to keep them cooler than the internal body temperature. Conversely, when exposed to cold, the cremaster muscle contracts to pull the testes closer to the body to maintain warmth.

This function is vital for spermatogenesis, as sperm production is most efficient at lower temperatures than those found in the core body. The adjustment of the testes’ position through the action of the cremaster muscle is an important physiological response for male reproductive health.