Skin secretions

Overview of skin secretions in humans and other animals

Overview

Diagram of a sweat gland, a key component in skin secretion.

Skin secretions refer to the various substances produced and released by the skin of humans and other animals. These secretions play crucial roles in maintaining skin health, regulating body temperature, and providing a barrier against pathogens. The primary types of skin secretions include sweat, sebum, and specialized secretions in certain animals.

Types of Skin Secretions

Sweat

Sweat is a watery fluid produced by the sweat glands located in the dermis layer of the skin. There are two main types of sweat glands: eccrine sweat glands and apocrine sweat glands.

• Eccrine sweat glands are distributed throughout most of the body and are primarily responsible for thermoregulation. They secrete a clear, odorless fluid composed mainly of water and salts, which evaporates to cool the body.

• Apocrine sweat glands are found in specific areas such as the armpits and groin. These glands secrete a thicker fluid that, when broken down by bacteria on the skin, can produce body odor.

Sebum

Sebum is an oily substance secreted by the sebaceous glands associated with hair follicles. It helps to lubricate and waterproof the skin and hair, providing a protective barrier against external elements. Sebum also has antimicrobial properties that help protect the skin from infections.

Specialized Secretions

In addition to sweat and sebum, some animals have specialized skin secretions. For example, amphibians produce mucus that helps keep their skin moist and can contain toxins to deter predators. Certain mammals, such as skunks, have specialized glands that produce strong-smelling secretions used for defense.

Functions of Skin Secretions

Skin secretions serve several important functions:

• Thermoregulation: Sweat helps regulate body temperature through evaporative cooling.
• Protection: Sebum and other secretions form a barrier that protects against environmental damage and microbial invasion.
• Hydration: Secretions help maintain skin hydration by preventing excessive water loss.
• Communication: In some species, skin secretions play a role in communication, such as marking territory or attracting mates.

Clinical Significance

Abnormalities in skin secretions can lead to various skin conditions. For example, overproduction of sebum can contribute to acne, while insufficient sebum can result in dry, flaky skin. Disorders of sweat glands, such as hyperhidrosis (excessive sweating) or anhidrosis (lack of sweating), can affect thermoregulation and skin health.

Related Pages

• Sweat gland
• Sebaceous gland
• Skin
• Thermoregulation
• Acne