• Question: How is Hair formed?

    Asked by bob skippy and layla legit to Hephzi, Imogen, Jen, Jennifer, Tom on 17 Mar 2015.
    • Photo: Thomas Barrett

      Thomas Barrett answered on 17 Mar 2015:

      The hair follicles are rooted in the scalp, and the hair has two parts: the hair bulb and the hair shaft.

      It is in the bulb, located at the base of the hair root, that the cells proliferate, thanks to the essential provision of oxygen, nourishing substances and mineral salts transported by the tiny capillaries.

      Gradually pushed upwards, these cells become loaded with keratin, a protein rich in sulphurous amino acids (cysteine and methionine) to form the hair we see. This is composed of three concentric layers of cells:

      • The medulla, in the centre, is formed of cells with no nucleii and very little pigment.

      • The cortex is composed of cells with plenty of keratin and pigments which determine the hair colour. It guarantees the hair’s rigidity and strength.

      • The cuticle, the outer layer, is composed of flattened cells, superimposed like the tiles on a roof. It protects the hair’s internal structure: it plays a barrier role that enables the hair to combat external attack and maintain a satisfactory level of moisturisation. It is therefore vital for the hair to remain healthy.

    • Photo: Imogen Napper

      Imogen Napper answered on 17 Mar 2015:

      Whether hair is growing out of your head, arm, or ankle, it all rises out of the skin in the same way. It starts at the hair root, a place beneath the skin where cells band together to form keratin (the protein that hair is made of). The root is inside a follicle which is like a small tube in the skin.

      As the hair begins to grow, it pushes up from the root and out of the follicle, through the skin where it can be seen. Tiny blood vessels at the base of every follicle feed the hair root to keep it growing. But once the hair is at the skin’s surface, the cells within the strand of hair aren’t alive anymore. The hair you see on every part of your body contains dead cells. That’s why it doesn’t cause pain when someone cuts your hair with scissors!

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