What was Griffith’s hypothesis?
Through a series of experiments, Griffith established that the virulence of the S strain was destroyed by heating the bacteria. … Based on these observations, Griffith hypothesized that a chemical component from the virulent S cells had somehow transformed the R cells into the more virulent S form (Griffith, 1928).
What type of molecule does the transforming principle contain?
DNA is identified as transforming principle. Each molecule contained DNA and protein. The chemical elements in the transforming principle were more similar to DNA.
What is the biochemical nature of transforming principle?
Oswald Avery, Colin MacLeod, and Maclyn McCarty showed that DNA (not proteins) can transform the properties of cells, clarifying the chemical nature of genes. Avery, MacLeod and McCarty identified DNA as the “transforming principle” while studying Streptococcus pneumoniae, bacteria that can cause pneumonia.
What was the transforming principle isolated in Griffith’s experiment quizlet?
Result: Griffith’s transforming principle is DNA
When labeled bacteriophages infect unlabeled bacteria, radioactive S stays on outside of bacteria, P found inside.
What did Griffith’s experiment show quizlet?
What did Griffith’s experiment show? Showed genetic material could be passed between bacteria and cause a change. … But when they treated the heat-killed LETHAL bacteria with enzymes to destroy DNA there was NO transformation and the mice lived! DNA was the molecule that caused the genetic change.
What evidence from Griffith’s investigation suggested that there was a transforming principle?
What evidence suggested that there was a transforming principle? When the mice died and Griffith found live S bacteria in blood samples from the dead mice! Griffith concluded that some material must have been transferred from the heat-killed S bacteria to the live R bacteria.
How did the transformation experiments of Griffith differ from those of Avery and his associates?
Griffith experiments could not characterize the transforming matter. Avery could isolate pure DNA showed that it is responsible for transformation.
What conclusions did Griffith make based on his experimental results?
Griffith concluded that something had passed from the heat-killed S strain into the live R strain and transformed it into the pathogenic S strain. He called this the transforming principle (Figure 2). These experiments are now known as Griffith’s transformation experiments.
How did Bacterial transformation occur in Griffith’s famous experiment?
In Griffith’s experiment, he mixed heat-killed S-strain bacteria with live, harmless bacteria from the R-strain. When this mixture was injected into mice, the mice developed pneumonia, died. … He was able to conclude that genes from the harmful bacteria transferred to the harmless bacteria, and transformed them.