But the acceleration it produces on the elephant and on the mass, are in an inverse ratio of their masses.

但这个力使大象和物体产生的加速度,与它们的质量成反比

耶鲁公开课 - 基础物理课程节选

Well, you could think about the cell wall of a bacterium as its skeleton, it's what protects it from mechanical forces that are out in the world.

你可能认为细菌的细胞壁,就像骨骼一样,使其免受,外界机械力的伤害

耶鲁公开课 - 生物医学工程探索课程节选