Human Scalp

In humans, the scalp is a specialized area of skin on top of the head, usually covered with hair in both sexes. It consists of three layers: a layer of skin, an underlying layer of tissue and blood vessels, and the occipitofrontalis muscle, which raises the eyebrows, stretching from the top of the eyebrows to the back of the head. The scalp covers most of the head, starting at the top of the forehead, and contains as many as 150,000 hair follicles.