They're divided lengthwise into segments called sarcomeres, which contain two even tinier strands of protein — two different kinds of myofilaments called actin and myosin.

它们在纵向上被分成称为肌节的部分，其中包含两股更小的蛋白质——两种不同的肌丝称为肌动蛋白和肌球蛋白。

You'd also re-learn that your skeletal muscles are constructed like a rope made of bundles of protein fibers, and that the smallest strands are your actin and myosin myofilaments.

你还会重新了解到你的骨骼肌就像一根由成束蛋白质纤维组成的绳子，最小的链是你的肌动蛋白和肌球蛋白肌丝。