Anatomy of hair

anatomy of hair

A summary of hair anatomy

Hair anatomy is very complex and more detailed than one may think. Here is a quick summary:

The hair follicle is actually part of your skin. It’s basically a pouch from where the hair shaft emerges. The hair shaft is the visible hair you see on the top of your skin. So the hair shaft is what we humans call hair. I’m going to refer to the hair shaft as hair.

At the base of the follicle is the hair bulb. Cells divide and grow here to form the hair. Now at the base of the bulb is the Dermal Papilla. It contains blood vessels that provide nutrients to the growing hair.

The follicle is lined by both inner and outer sheaths. They protect and shape the growing hair. The Arrector Pili muscle attaches to the outer sheath. When we feel cold this muscle contracts causing the hair to stand up, known as goosebumps.

Just above the muscle lives the Sebaceous Gland. This produces Sebum, an oily secretion to the surface of the skin. Sebum protects the hair and acts as a natural conditioner. When the follicle or gland gets blocked by things like dead skin cells, pollution, makeup etc it causes what we call a blocked pore. So when you unblock the pore you’ll notice not only the release of sebum but also sometimes a hair as well.

A single hair has 3 parts: Medulla, Cortex and Cuticle. The Medulla and Cortex have pigment cells that give colour to your hair. The Cuticle is the outer and strongest part made up protein, called Keratin.

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