上气通大学 Shanghai Jiao Tong University 第一节遗传的物质基础 一、DNA作为遗传物质（略） Strain of Strain of Colony Colony Cell type Effect Cell type Capsule No capsule Smooth (S) Live S Rough(用 Live R strain strain (b) Live R strain Heat-killec Heat-killed 5 strain S strain Live S and R strains isolated from dead mouse Griffith转化实验 Figure 13.1 Grifith's Transformation Experiments.(a)Mice died of pneumonia when injected with pathogenic strains of S pneumococci. which have a capsule and form smooth-looking colonies.(b)Mice survived when injected with a nonpathogenic strain of R pneumococci.which No.8 lacks a capsule and forms rough colonies.(c)Injection with heat-killed strains of S pneumococci had no effect.(d)Injection with a live R strain and a heat-killed S strain gave the mice pneumonia,and live S strain pneumococci could be isolated from the dead mice. 学院陈峰Shanghai Jiao Tong University No. 8 上海交大生命学院陈峰 一、DNA作为遗传物质（略） 第一节 遗传的物质基础 Griffith转化实验