The skin is the largest organ in the body. It protects against heat, light, injury and infection. It also regulates body temperature; provides
sensory input for heat, touch and pain; and stores water, fat and vitamin D.
The skin has three layers:
Epidermis
Dermis
Subcutaneous layer
In addition to the skin, other soft tissues include muscle, fascia, tendons and ligaments and muscles.
The epidermis is the thin outer layer of the skin. This layer contains cells that continually divide, forming
new cells and replacing the old ones that are shed from the surface of the skin.
The dermis is the layer below the epidermis. It contains:
Blood vessels
Lymph vessels
Hair follicles
Sweat glands
The dermis is held together by a protein called collagen that gives the skin its strength and resilience. This layer also contains
pain and touch receptors.
The subcutaneous layer is the inner layer of the skin and is made up of a network of collagen and fat cells. It helps
conserve body heat and protect internal organs from injury by acting as a shock absorber.
Graphic illustration: LifeART(R) image, Copyright 1998, Lippincott Williams & Wilkins. All rights reserved.
