Skin is the body's largest organ, and along with hair, nails, glands and nerves, is part of the integumentary system, according to Oregon State University. ... In adults, skin accounts for about 16 percent of total body weight and covers a surface area of approximately 22 square feet (2 square meters).
The primary function of the skin is to act as a barrier. The skin provides protection from: mechanical impacts and pressure, variations in temperature, micro-organisms, radiation and chemicals.
Other biological molecules that contain the element of N would be nucleic acids such as DNA and or RNA. There are found in the nucleotides that constitute or make up these nucleic acids.
