9A: Inheritance and variations Lesson 4: History of DNA discovery

Learning objective State the roles played by Watson, Crick, Wilkins and Franklin in the development of the DNA model

Scientific Process Through experiments scientists knew DNA was made of nucleotides that appeared in set ratios They did not know Exactly how the molecules were joined together Wanted to know how DNA could make exact copies of itself

Maurice Wilkins 1916-2004 Born in New Zealand Moved to England when he was 6 1938- graduated from St. John’s College in Cambridge Worked on improving radar 1943- Manhattan project (atomic bomb) Back in UK- started x-raying biological molecules (DNA) Rosalind Franklin joined him in this project 1962- Noble Prize in Medicine with Watson and Crick

Rosalind Franklin 1920-1958 Wanted to be a scientist from a young age Difficult for girls at this time Studied chemistry and physics Studied the physical structure of coal Moved to France- learned x-ray diffraction techniques 1951- moved back to England to work with Wilkins took the 1st photo’s of DNA and predicted the helical structure of the molecule Died before she could be awarded the Noble Prize

James Watson 1928- Born in America Worked in Chicago, Indiana and Copenhagen Moved to Cambridge to work with Francis Crick Studied the structure of DNA Created the first model that explained replication and genetic codes 1962- Noble Prize in Medicine with Crick and Wilkins 1988-1992 leader and organizer of the Human Genome project

Francis Crick 1916-2004 Born in England Studied physics but switched to biology in 1947 Started working with Watson on DNA model 1962- Nobel Prize Continued work in genetics Changed focus and worked on brain research at Salk Institute in California

What they discovered

Task: comic strip- time line Create a comic strip or timeline poster of the famous people who helped us learn what the DNA molecule looks like (Watson, Crick, Wilkins and Franklin) This is an assessed piece of work based on how well you communicate your new knowledge- see rubric next slide

Marking rubric 0-2 The student does not reach a standard described by any of the descriptors 3-5 The student attempts to communicate scientific information using some scientific language. The student presents some of the information in an appropriate form using some symbolic or visual representation when appropriate. The student attempts to acknowledge sources of information but this is inaccurate 6-8 The student communicates scientific information using scientific language. The student presents most of the information appropriately using symbolic and/or visual representation according to the task. The student acknowledges sources of information with occasional errors 9-10 The student communicates scientific information effectively using scientific language correctly. The student presents all the information appropriately using symbolic and/or visual representation accurately according to the task. The student acknowledges sources of information appropriately.