This is the story. In 1950, Rosalind Franklin was a biologist that used X-ray crystallography to study the structure of DNA. She was specifically studying DNA fibers that had single DNA molecules. Because the technique of X-ray crystallography can only be applied to crystals, she had to crystallize the DNA molecules with salt to form crystal structures of DNA. She also had to adjust her X-ray crystallographer with a very small lens (micro-lens) to be able to take pictures of such small molecules. In 1952, she took a beautiful X-ray diffraction picture of DNA (below).
In 1953 Linus Paulin was a chemist and a X-ray crystallographer that published the wrong structure of DNA in The Proceedings of the National Academy of Sciences. He thought that DNA was a triple helix. Stephen Lawson says that Paulin’s triple-helical structure of DNA, “turn out to be one of the most famous mistakes in 20th-century science.”
At the same time, James D. Watson and Francis Crick were also doing research trying to figure out the structure of DNA. As soon as Watson knew about the work of Paulin, he took a copy of Paulin’s work and went to see his friend Wilkins. Wilkins was other scientist that was doing DNA diffraction research with Franklin. Wilkins always had conflicts with Franklin at work. He was provably jealous of Franklin’s work. That was provably the reason why he gave Watson the best X-ray refraction pictures of DNA that Franklin took (above). That picture showed that the structure of DNA was a double helix and not a triple helix like Paulin thought and published earlier. Watson and Crick reviewed the picture, studied it and created a double helix model of DNA. However, they had a little problem. The building blocks (bases) of their DNA model were sticking out. To correct it, they had to use the data from another scientist. The data they used was known as the Chargaff’s rules. Those rules were created by Erwin Chargaff and said that the building blocks of DNA (bases) are suppose to be inside the double helix or the backbone, not outside.When their model was fixed and reassembled, they published it in the journal Nature
In 1962, Wilkins, Watson and Crick received the Nobel Price for discovering the structure of DNA. Rosalind Franklin died of cancer of the ovary in 1958 and she did not get the Nobel Price.
In the twenty century, Franklin’s work was not well known. At that time, the newspaper, television and telephone were the only ways to know what was going on in the world. People could only trust the news papers, TV or journals about scientific discoveries. If they were suspicious or wanted to know about Franklin’s DNA diffraction work. They had to go to a library or try to find her original work. In the twenty century, technology was used mainly for communication purposes. But, today technology is used also for education. In fact, readers, students, parents, and everyone else can go online and find everything about Rosalin Franklin or the structure of DNA. People don’t need to be scientists to learn about science. The internet became such a huge network that a reader can access all kind of information from a computer.
Today, Franklin’s work and DNA information educate people everywhere. People can browse the web with their cell phones or they can find information of DNA even when we are in bed. Laptops, iphones, and now ipads allow individuals to access all the information about Watson & Crick that they want to learn. However, not all the information in the internet is accurate and can be used to educate readers about technology or DNA. Some information is not reliable and can confuse the readers. The challenge is that readers learn how to distinguish good from bad information and not to trust everything they read.
Sources of pictures:
"Molecular Structure of Nucleic Acids." Nature. Web. 13 Feb 2010.
"Rosalind Franklin Photo 51." Wikipedia. Web. 13 Feb 2010.
"The Triple Helix." Linus Pauling Institute Research Report. Web. 13 Feb 2010.
Posts
No comments:
Post a Comment