Again, I'm just trying to highlight things you already know a little bit about, the book describes the details.

这里我也只是,强调一些你可能已略知一二的知识,你们教材里面有相关的细节

耶鲁公开课 - 生物医学工程探索课程节选

Again, more details in your book if you want to read that.

同样,你要知道更多细节可以看书

耶鲁公开课 - 生物医学工程探索课程节选

These details aren't important, it is described in your book, but the thing that is important to know is that diffusion occurs fast over short distances, but because of the physics of diffusion it occurs slowly over longer distances.

这些具体细节无关轻重,书上都有,重点是你要明白,距离越短扩散越快,由于扩散现象的物理特性,距离越长扩散越慢

耶鲁公开课 - 生物医学工程探索课程节选