keratin

In fact, it´s keratin which makes them flexible and without it they would be very rigid.

实际上，是角蛋白使它们变得富有弹性，并且没有角蛋白的话，它们会变得非常坚硬。

Now hair, whatever it is for and wherever it is on the human body, is composed mainly of a protein called keratin.

不管毛发是用来做什么的，也不管它在人体的哪个部位，它都主要由一种叫做角蛋白的蛋白质组成。

The alpha helix is found in muscle protein and keratin.

α螺旋存在于肌肉蛋白和角蛋白中。

Keratin is the major protein in hair and nails.

角蛋白是毛发和指甲中的主要蛋白质。

The main component of hair is known as keratin .

头发的主要成分被称为角蛋白。