the discovery of DNA

Johannes Miescher

Johannes Miescher

Discovered DNA

DNA is not a protein

DNA is rich in nitrogen and phosphorous

Frederick Griffith

Studied 2 bacteria, 1 harmless, 1 harmful, and found that heat destroyed a bacteria’s ability to cause disease but not its hereditary function

found the function of DNA

Avery, MacLeod & McCarty

Discovered that the hereditary substance must be a nucleic acid

Came to the conclusion that it was DNA by using specific enzymes that destroyed DNA and RNA

Alfred Hershey & Martha Chase

Used bacteriophage, a virus that infects bacteria

Carries hereditary material

Proved that the material bacterophage injects into is DNA not a protein

Erwin Chargaff

Amounts of Thymine and Adenine are identical in any DNA molecule

Amounts of Cytosine and Guanine are identical in any DNA molecule

Proportions of those bases may vary

James Watson & Francis Crick

Theorized the helixical/coiled pattern of DNA

Built the first accurate model of DNA

Rosalind Franklin

Used an x-ray to decipher shape, size, and spacing between elements

Identified a repeating pattern and that DNA was LONG