What is hair made from and why does the funny bone get on our nerves?

We explore some of the curious questions that science can answer

Hard cell: a strand of hair is stronger than nylon or copper wire (Getty/iStock)

What is hair made of?

Hair is made from cells called epithelial cells, which are arranged in three layers. The innermost layer is the medulla, the middle layer is the cortex and the outer layer is the cuticle. The medulla is mainly soft keratin (a protein) and the cortex and cuticle are mainly hard keratin. This structure has great strength – a strand of hair is stronger than an equally thick strand of nylon or copper wire.

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