The function of the integumentary system in thermoregulation involves maintaining body temperature and protecting internal structures. Comprising the skin, hair, nails, and associated glands, this system plays a critical role in regulating heat loss or retention. For instance, blood vessels in the skin can dilate to release heat or constrict to preserve warmth. Sweat glands also facilitate cooling through evaporation. Additionally, the integumentary system provides a barrier against pathogens and helps prevent dehydration. By integrating these functions, the integumentary system is essential for homeostasis and overall health in organisms.