Which gland contains approximately two million secretory units on an adult body?

The eccrine gland is known for its abundance in the human body, containing approximately two million secretory units in adults. These glands are primarily responsible for regulating body temperature through sweat production, which is essential for thermoregulation. Eccrine glands are distributed widely across the skin, particularly in areas like the forehead, palms, and soles of the feet.

The structure of eccrine glands includes coiled tubular units that are connected to the surface of the skin through ducts. When the body temperature rises, these glands secrete water and electrolytes onto the skin surface, where evaporation cools the body down. This process is vital for maintaining thermal homeostasis, especially during physical activities or in hot environments.

Understanding the role and distribution of eccrine glands is essential for anyone in the beauty therapy or aesthetician field, as skin care and treatment regimens can be significantly impacted by individual sweat levels and skin hydration.