Sweat glands are tubes in which sweat is produced and then transported to the surface of the skin. Many people think of sweat as rather unpleasant, but it does serve an important purpose. Also referred to as perspiration, sweat serves to cool the body off. To perform this purpose well, sweat glands are spread all over the body, with the exception of places like the lips, parts of the genitals, and a person’s nipples. In all, each person typically has more than two million sweat glands.
Each gland consists of a hollow tube, which is long and coiled in a ball at its base. The coiled base of the gland is located in the dermis, which is the second layer of skin. A person’s sweat is produced in this coiled part of the gland. Then, the long section of the gland that extends from the coiled portion, often referred to as a duct, allows the sweat to move from the base toward the surface of the skin. In order to exit the gland and move out to the skin, however, the sweat needs an opening through which to move; this opening is called a pore, which is a tiny hole on the skin.
The human body has two different types of sweat glands. First, there are eccrine glands, which are the most common type. They are located all over the body, especially in a person’s forehead, neck, back, palms, and feet. These glands produce sweat when a person becomes hot because of external heat, fever, exercise, and even emotional upset. The sweat glands in the palms and soles of the feet are particularly likely to react in stressful situations.
The apocrine glands, on the other hand, are a bit different. The ending points of these glands are usually not pores; these glands end in hair follicles instead. As such, they are usually concentrated in areas that have hair, such as the armpits, around the anus, and the external genital areas. These glands respond mostly to emotional stress of some type and also produce sweat when a person is upset or sexually excited.
Interestingly, the apocrine glands may be responsible for much of a person’s body odor after forgetting deodorant or following intense exercise. This is because the secretions from these glands have a scent. In fact, apocrine glands are sometimes referred to as scent glands.