Lynn Waldrop – Rebuild Your Body 2016 – Integumentary System

The integumentary system, or skin, is the largest organ in the body. Besides the skin, it comprises the hair and nails as well, which are appendages of the skin. In humans, this system accounts for about 15 percent of total body weight. Skin and hair provide protection from harmful ultraviolet radiation and the skin guards against sunburn. It also waterproofs, cushions and protects the body from infection. The integumentary system excretes wastes and regulates body temperature. The skin is the body’s initial defense against bacteria, viruses and other microbes. Human skin color is determined by the interaction of melanin, carotene and hemoglobin.