They're small molecules that - whose principal function in the body is to carry signals from one cell in the nervous system to another.

它们都是小分子,在体内主要功能是在,神经系统内将信号,从一个细胞传导到另一个细胞

耶鲁公开课 - 生物医学工程探索课程节选

That's what leads to some of the complexity of function of the nervous system.

这就是导致,神经系统功能多样性的原因

耶鲁公开课 - 生物医学工程探索课程节选

So organs are made up of combinations of tissues where all the tissues are collections of cells that are doing some function, nervous tissue, muscular tissue, epithelial tissue, those are examples of tissues that form organs.

所以器官是由各种组织组合而成,所有的组织都是,具有某些功能的细胞集合,神经组织,肌肉组织,上皮组织,这些都是由组织构成器官的例子

耶鲁公开课 - 生物医学工程探索课程节选