What it does • protection against disease ( it acts as a first defense against disease causing particles, due to the fact most cant get through unopened skin) • sensory response (specialized nerve cells sense and relay info to the brain) • formation of vitamin D (formed by ultraviolet light in fat molecules in your epidermis) • maintaining body temperature ( blood vessels in the skin can help to hold or release heat maintaining a constant temperature) • waste exchange (sweat glands in the skin release waste in the sweat)

Integumentary System Organs

The integumentary system forms a protective barrier between the external environment and the inner tissues. Other than that, the integumentary system organs work together to provide insulation and help in excreting waste from the body. To know more about the same, read on...

Skin which is the largest organ of the body is also the principal organ of the integumentary system. Other than the skin, nails, hair, scales and feathers that are actually extensions of the skin are also sometimes studied as integumentary system organs. All these structures together provide protection to the inner tissues of the body. Other than protection, the organs have other functions as well. Let us know more about them in detail in the following paragraphs.

Integumentary System Functions

Protection: The most important function of the integumentary system is protection. The organs of the integumentary system form a water-proof layer over the body that also works as a physical barrier against microorganisms entering the body and causing integumentary system diseases.

Homeostasis: Environmental conditions outside the body keep changing. However, for the organs of different human body systems to work properly, particular environmental conditions are required. Homeostasis refers to regulating internal environment of the body to maintain stable conditions. This is achieved by the integumentary organs which ensures proper functioning of all the organs of the body.

Sensory Organ: The skin has a large number of nerve openings that help us in perceiving the sense of touch, pressure, pain and changes in temperature.

Excretion: Toxic wastes are excreted by the skin in the form of perspiration.

Organs in the Integumentary System

We already know what organs are in the integumentary system. Now let us concentrate on the structure and function of each organ individually.

Skin: The skin is the main organ of the integumentary system. It is made of two dermal layers. They are: • Epidermis: It is the outermost layer of the skin. It forms the waterproof barrier over the body. • Dermis: It lies below the epidermis. It contains blood vessels, hair follicles and various glands.
Although studied along with the different layers of the skin, hypodermis is actually not a part of the largest organ of the body. In fact it is a subcutaneous layer (layer that lies below the skin) that attaches the skin with the underlying tissues. 50% of the hypodermis is fat which provides padding and insulation for the body. The glands present in the skin are the sweat glands and the sebaceous glands. The sweat glands release sweat which is the primary way of cooling the body.The sebaceous glands on the other hand release sebum - an oily substance that lubricates the skin and the hair.

Hair: One of the defining characters of all mammals, hair is formed from the hair follicles that is found all over the skin. Hair is mainly keratin. Each hair strand can be divided into three layers that lie one inside the other. The innermost layer is the medulla which is made up of loose cells and air spaces. Outside this is second layer - the cortex which is made of densely packed keratin. The outermost layer is the cuticle which is made up of cells overlapping like scales. Hair traps air around the body that acts like an insulating layer. Hair lining the nasal chambers and those that appear