Homogenize Centrifuge Heat-kill cells Recover llls filtrate llS cells spun to Extract carbohydrates bottom of tube lipids, and proteins IllS cells in liquid culture medium Treat with Treat with Treat with deoxyribonucle ribonuclease proteas Assay for Transformation IIR cells IIR cells IR cells IIR cells DNase-treated RNase-treated Protease-treated IllS filtrate llIS filtrate lIIS filtrate Ills filtrate No transformation Transformation Transformation Transformation occurs occurs occurs occurS IIR cells IIR cells IIR cells IIIs cells llIs cells sa S cells Conclusion Conclusion: onclusion Control: Active factor is DNA Active factor is not RNA Active factor is not protein Ills contains active factor tais IllS cells BB942 IIR cells 美国学者 Avery等证明转化因子是DNA。 Summary of Averys experiment which demonstrated that DNa is the transforming principle美国学者Avery等证明转化因子是DNA。Summary of Avery, s experiment which demonstrated that DNA is the transforming principle