Often that signal gets amplified so it can be used, same thing happens inside cells and there's some output that's generated.

通常这些信号要放大后才会产生作用,诱发细胞内发生一些变化,并产生某种输出信号

耶鲁公开课 - 生物医学工程探索课程节选

That's what's illustrated here with the end result being that there's some change in the life of the cell.

这里显示的是,在信号放大传递后,细胞内发生的变化

耶鲁公开课 - 生物医学工程探索课程节选

This is commonly used in the immune system as well, but it's a way of amplifying a signal.

免疫系统也常使用这种方法,但这主要是一种放大信号的方式

耶鲁公开课 - 生物医学工程探索课程节选

A reaction performed by one enzyme creates a product that stimulates another enzyme that creates a product, and stimulates another enzyme, and through this cascade of reactions you amplify and carry the signal forward.

一种酶催化生成的产物会活化另一种酶,而它催化的产物又能激活其他酶,催化反应生成另一种产物,通过这层层反应,信号被放大,并不断向前传递

耶鲁公开课 - 生物医学工程探索课程节选