Final answer:
The culture injected with DNase in the Avery, MacLeod, and McCarty experiments was unable to produce transformed bacteria, supporting the conclusion that DNA is the transforming principle. DNA degradation prevented transformation, while degradation of other components did not.
Step-by-step explanation:
The culture injected with DNase (an enzyme that degrades DNA) in the Avery, MacLeod, and McCarty experiments was unable to produce transformed bacteria. This experiment was conducted to determine the transforming principle responsible for converting non-virulent bacteria into virulent bacteria. The scientists used enzymes to degrade different components of the S strain, including DNA, proteins, and RNA, and examined the ability of each mixture to transform the R strain.
They found that when DNA was degraded, the resulting mixture was no longer able to transform the bacteria. This led the scientists to conclude that DNA was the transforming principle. On the other hand, degradation of other components, such as RNAs and proteins, did not prevent transformation. Therefore, the culture injected with DNase (which degrades DNA) was not able to produce transformed bacteria, supporting the conclusion that DNA is the genetic material responsible for transformation.