The integumentary system serves as the body’s protection from the external environment. It retains body fluids, eliminates waste products, and regulates the body temperature.

The **integumentary system** functions as a barrier against the external environment and the body. Moreover, this system also helps in temperature regulation, removal of waste materials, and protection against the UV rays of the sun.

The system is composed of various tissues and organs that work together in order to achieve its major functions.

1. The skin contains two layers of tissues (epidermis- the outer layer and dermis- the inner layer)
2. Hair – which gives additional protection to the skin
3. Nails
4. Glands – Sebecaeous and sweat glands.

The **epidermis** is the outer layer of the skin composed of two layers in which the outer layer is comprised of dead skin cells and the inner layer is comprised of proliferating cells. These proliferating cells push the older cells to the surface of the epidermis, and as it moves upward the cells tend to disintegrate and die.

The **dermis** is the layer beneath the epidermis. This layer of the skin is composed of collagen fibers, blood vessels, nerve endings, follicles, and smooth muscles. The dermis also contains the two important glands of the skin which are the sebaceous gland and sweat gland.

The **skin** connects and interacts with other body systems in order to balance and maintain homeostasis. The skin specifically helps in regulating the body temperature by regulating the blood vessels present in the dermis. During hot weather, the blood vessels in the dermis area dilate to transport the heat from the body to the skin, while during cold weather, the blood vessels constrict conserving the heat in the body.

Moreover, the dermis of the skin contains sweat glands that regulate the perspiration in the body. As the sweat is released it will evaporate and the heat and waste materials are also being let go from the body.

As the hair and the nails grow, the part above the skin is composed of dead cells that are covered in keratin.

The skin comprises two layers of tissues that function as a barrier between the body and the external environment. One of the layers called the **epidermis** is the outer of the skin, and it is composed of a layer of continuously living and dividing cells, along with free nerve endings. This is the reason why we experience pain every time we cut ourselves in this area of our body.

The **nails** on the other hand, are created from the nail root. As the cells in the nail root divide and form this structure the matured portion moves out and detaches away from the nerve endings and live cells. This is why we don’t experience any pain when we trim our nails– because this portion of the nails is considered dead tissues.