%@LANGUAGE="JAVASCRIPT" CODEPAGE="1252"%>
Data In
|
Genetic 342 A&B
Kenneth G Wilson
Professory of Botany |
Data in is like hind-sight it is 20:20 it is what is known at the time
Evidence known and used by Watson and Crick in 1953 to construct a model of DNA
- In 1868 Friedrick Miescher first studied nuclein or nucleic acid.
- In 1910 Phoebus A. Levene proposed the tetranucleotide hypothesis.: A = C = G = T.
- Base Composition Studies
- Between 1949-53 Erwin Chargaff developed some rules for DNA - A=T, C=G, Purines + Pyrimidines etc.
- Between 1938-47 William Atsbury determines a 3.4 Angstrom periodicity
- Between 1950-53 Rosalind Franklin and Maurice Wilkins verify Atsbury and suggest a helix of some type.
- Thus, X-Ray Diffraction Analysis gives evidence that the unit cell is about 20 by 34 Angstroms with repeats at 3.4 Angstroms and that there is some type of helix.
- Proteins have an alpha helix structure as proposed by Linus Pauling.
- The chemical structure of the Sugars and the Bases
|
This is our friend Oliver the parrotlet,
Oliver is a true parrot,
the smallest in the world. |