Hair root.Coloured scanning electron micrograph (SEM) of the root and part of the shaft of a plucked human hair. The base of the hair is known as the hair bulb and is the site of hair growth. It is usually located in a hair follicle in the skin, at the base of which is an area called the dermal papilla. This region is supplied with blood, which gives nourishment for the production of new hair. As new cells form in the follicle they die, become keratinized and pigmented, and get pushed out to form the shaft of the hair. Human hair contains two types of DNA. Nuclear DNA is found in the tissue at the root of a strand of hair while mitochondrial DNA is found in the shaft of hair itself. Initially, only nuclear DNA could be extracted and analyzed, but today, both types of DNA can be used to help identify individuals. Magnification: x130 when printed 10cm high.