Concept 19 The DNA molecule is shaped like a twisted ladder.
James Watson, 2 years old.
James Watson, 10 years old.
James Watson on a vacation in the Italian Alps, 1951.
April 1, 1953 diary entry of Gerard R. Pomerat, Rockefeller Foundation science officer. Pomerat was on a visit to the Cavendish labs and describes the excitement of Watson and Crick's work.
James Watson (R) and Francis Crick (L) walking along the banks at Cambridge University.
Francis Crick at Cavendish, next to an X-ray tube.
Erwin Chargaff, 1947. He was the first to accurately measure nucleotide amounts in DNA.
The six feet tall metal DNA model made by Watson and Crick in 1953.
1962 Nobel Prize winners: (L-R) Maurice Wilkins (Physiology or Medicine), M. Perutz (Chemistry), Francis Crick (Physiology or Medicine), J. Steinbeck (Literature), James Watson (Physiology or Medicine), J. Kendrew (Chemistry).
If Erwin Chargaff had used E. coli as a source of DNA, he would have "proven" Levene's tetranucleotide theory. E. coli has almost equal amounts of all four nucleotides.
Why is DNA double stranded? Wouldn't it be easier to access the genetic information if there were only one strand?
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James Watson, 2 years old.
DNA and proteins are key molecules of the cell nucleus.
One gene makes one protein.
A gene is made of DNA.
Bacteria and viruses have DNA too.
The DNA molecule is shaped like a twisted ladder.
A half DNA ladder is a template for copying the whole.
RNA is an intermediary between DNA and protein.
DNA words are three letters long.
A gene is a discrete sequence of DNA nucleotides.
The RNA message is sometimes edited.
Some viruses store genetic information in RNA.
RNA was the first genetic molecule.
Mutations are changes in genetic information.
Some types of mutations are automatically repaired.