What is the primary function of sweat glands?

The primary function of sweat glands is to regulate body temperature. Sweat glands produce sweat, which is composed mainly of water and some salts. When the body temperature rises, such as during exercise or in response to heat, the nervous system stimulates these glands to produce sweat. As sweat evaporates from the skin's surface, it effectively cools the body down, helping to maintain a stable internal temperature. This process, known as evaporative cooling, is essential for thermal regulation and plays a critical role in preventing overheating.

In contrast, the other options describe different functions that are not directly associated with sweat glands. While storage of fat is primarily managed by adipose tissue, protection from UV radiation is typically provided by skin pigmentation and other protective mechanisms, and hormone secretion is a function of endocrine glands rather than sweat glands. Understanding the distinct role of sweat glands in thermoregulation is crucial for recognizing how the body maintains homeostasis in response to varying environmental conditions.