dartos

muscle

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Last updated

June 25, 2026

Quick Summary

The dartos is a layer of smooth muscle tissue found in the wall of the scrotum. This muscle is involuntary and plays a role in regulating the temperature of the testes. When exposed to cold, the dartos muscle contracts, causing the scrotum to shorten and wrinkle, which helps to keep the testes warm. Conversely, when exposed to warmth, the dartos relaxes, allowing the scrotum to become smoother and less tightly drawn, which aids in cooling the testes. This temperature regulation is crucial for the production of viable sperm.12

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human reproductive system
The scrotum
…layer of involuntary muscle, the dartos, which can alter the appearance of the scrotum. On exposure of the scrotum to cold air or cold water, the dartos contracts and gives the scrotum a shortened, corrugated appearance; warmth causes the scrotum to become smoother, flaccid, and less closely tucked in around…
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…layer of involuntary muscle, the dartos, which can alter the appearance of the scrotum. On exposure of the scrotum to cold air or cold water, the dartos contracts and gives the scrotum a shortened, corrugated appearance; warmth causes the scrotum to become smoother, flaccid, and less closely tucked in around…
Read More