Balderdash Example Griffith’s Transformation Experiment Ever since Edward Jenner invented the first vaccine in 1796 scientists have been working to vaccinate the world against all known diseases. Frederick Griffith wanted to save the world from pneumonia, a disease that was killing off much of Europe during the 1920’s. He didn’t build the pneumonia vaccine, but he did accidentally discover one of the most important concepts in bacterial survivability: Griffith discovered the principle of bacterial transformation. (In other words, why bacteria can fight off antibiotics) Griffith’s Transformation Experiment In 1928, Frederick Griffith was working with mice and two strains of Streptococcus pneumoniae One strain was “rough” in appearance and non-virulent, meaning that it wasn’t strong enough to hurt it’s host One strain was “smooth” in appearance and virulent. It was deadly to anyone who contracted the strain. The smooth strain looked smooth because it lacked a special protein coat that was rough in appearance and acted as a beacon summoning the mice’s immune systems. When injected with the rough (non-virulent) strain, mice lived When injected with the smooth (virulent) strain, mice died. Both as expected. Griffith’s Transformation Experiment Next, Griffith boiled the deadly, smooth strand of bacteria to kill it. He then injected mice with the deadly but boiled strand. Once again, as expected, the mice still lived. Finally, he injected the mice with BOILED smooth strands and LIVING rough strands The smooth strands are normally deadly, but Griffith had boiled them so they were not dangerous anymore. The rough strands were never deadly even when they were alive. Neither should have killed the mice. Yet this time, the mice died. Griffith’s Transformation Experiment The deadly strand had been killed. But the non- virulent strand had approached the dead virulent cells and absorbed their genetic material. Even though the virulent cells were dead, the genetic material from the virulent cells were still present. The living, non-virulent cells grave-robbed the genes from the dead, virulent cells and used those genes to learn how to become virulent too. Griffith’s Transformation Experiment Griffith’s experiment proved the concept of transformation, which means cells can take genetic material from other cells and use them for themselves The “next experiment” for Griffith was to answer the following question: what was the molecule that the living cells grabbed from the dead cells? (At this time, no one knew about DNA, genes, or chromosomes yet) What is the fake fact? #1: One strain was “rough” in appearance and non-virulent, meaning that it wasn’t strong enough to hurt it’s host #2: One strain was “smooth” in appearance and virulent. It was deadly to anyone who contracted the strain. #3: The smooth strain looked smooth because it lacked a special protein coat that was rough in appearance and acted as a beacon summoning the mice’s immune systems. #4: Neither should have killed the mice. Yet this time, the mice died. #5: The living, non-virulent cells grave-robbed the genes from the dead, virulent cells and used those genes to learn how to become virulent too.
Drum roll… What is the fake fact? #1: One strain was “rough” in appearance and non-virulent, meaning that it wasn’t strong enough to hurt it’s host #2: One strain was “smooth” in appearance and virulent. It was deadly to anyone who contracted the strain. #3: The smooth strain looked smooth because it lacked a special protein coat that was rough in appearance and acted as a beacon summoning the mice’s immune systems. #4: Neither should have killed the mice. Yet this time, the mice died. #5: The living, non-virulent cells grave-robbed the genes from the dead, virulent cells and used those genes to learn how to become virulent too.
The smooth strand actually had a smooth protein coat that protected the cell from the mice’s immune systems