SKELETON SYSTEM

The skin is the largest organ of the body, with a total area of about 20 square feet. The skin protects us from microbes and the elements, helps regulate body temperature, and permits the sensations of touch, heat, and cold.
Skin has three layers—

• The epidermis, the outermost layer of skin, provides a waterproof barrier and creates our skin tone.
• The dermis, beneath the epidermis, contains tough connective tissue, hair follicles, and sweat glands.
• The deeper subcutaneous tissue (hypodermis) is made of fat and connective tissue.

Melanin is a pigment that gives human skin, hair, and eyes their colour. Dark-skinned people have more melanin in their skin than light-skinned people. Melanin is produced by cells called melanocytes.