Carbon, at least on Earth, is the primary building block of life.

碳，至少在地球上，是构成生命的主要元素。

A Universe Within The brain's primary building blocks are neurons--specialized cells that transmit information through electrical and chemical signals.

大脑的主要组成部分是神经元——通过电信号和化学信号传输信息的特殊细胞。