【答案解析】操纵子(operon)：是原核生物基因表达和调控的一个完整单元，其中包括结构基因、调节基因、操作子和启动子。B. Lewin在(Genes中这样定义操纵子：“Operon is a complete unit of bacterial gene expression and regulation, incklding structural genes, regtdator gene(s), and control elements in DNA recognized by regulator gene product(s).”