Chapters 2 and 4 are really reviews of things that you probably already know something about, so they're reviews of basic chemistry.

第二章和第四章是对,一些你可能已经知道的,基础化学,蛋白质及生物化学知识的复习

耶鲁公开课 - 生物医学工程探索课程节选

And if you've forgotten about proteins and what their structure is you can go to Chapter 4 and read sort of a brief review of protein biochemistry.

如果你们忘记了蛋白质及结构的相关知识,就去读第四章,关于蛋白质生物化学的简短综述

耶鲁公开课 - 生物医学工程探索课程节选