How do the eccrine sweat glands and apocrine sweat glands differ?

Embryologically, eccrine glands derive from the epidermis and are not part of the pilosebaceous unit. The eccrine sweat glands function in temperature regulation via secretion of sweat, a combination of mostly water and electrolytes, which evaporates and cools the skin. Their ducts pass through the dermis and epidermis to empty directly onto the skin surface. Eccrine glands are located everywhere on the skin surface except on modified skin areas, such as the lips, nail beds, and glans penis. Eccrine sweat glands are found only in higher primates and horses.




Apocrine glands originate from the same hair germ that gives rise to the hair follicle and sebaceous gland. The apocrine duct empties into the follicle above the sebaceous gland. Their anachronistic function is to produce scent. They are located primarily in the axillae and perineum, and their activity is sex hormone–dependent. The breast and cerumen glands are both modified apocrine sweat glands.