信使

The messenger conveys the urgent news to the village chief.

信使把紧急消息传达给村长。

The messenger brought your note today.

信使今天带的信。

Cistron A unit of function, i.e. a segment of DNA that determines a single polypeptide chain of a protein molecule or a messenger RNA molecule.

是一个功能上的结构，它是决定蛋白质分子的一简单多肽链或信使RNA分子的DNA片断。