Whereas old dependency theory was Marxist in presentation, but nationalist in orientation, seeking to combine a theory of class struggle with a nationalist âthird worldistâ ideology, the new dependency theory is institutionalist in its analysis and political orientation.
Griffith concluded that the type II-R had been transformed into the lethal III-S strain by a transforming principle that was somehow part of the dead III-S strain bacteria. Today, we know that the transforming principle Griffith observed was the DNA of the III-s strain bacteria. While the bacteria had been killed, the DNA had survived the heating process and was taken up by the II-R strain bacteria. The III-S strain DNA contains the genes that form the protective polysaccharide capsule.
In his experiment, Griffith found that if the dangerous S bacteria strains of Streptococcus pneumonia (that he put in a capsule to stop the bodies defense systems) were injected into mice, then the mice quickly died from pneumonia because of the bacterial poisoning.he S strain was then heated to kill the bacteria, and the dead strain was injected into mice, where it didn't have any effect. However, when the dead S strain was mixed with alive R strain bacteria, it did kill the mice.