Genetic Discoveries Timeline

Timeline created by
  • Gregor Mendel

    Gregor Mendel
    Experiment: He test crossed pea plants.
    Contribution: He figured out that parents pass on discrete genes. Genes retain their individuality generation after generation
  • William Bateson and Reginald Punnett

    William Bateson and Reginald Punnett
    Experiment: They were working with flower color and pollen shape in peas. They crossed double heterozygous plants.
    Contribution: They discovered Punnett squares and linked genes
  • Thomas Hunt Morgan

    Thomas Hunt Morgan
    Experiment: He observed the inheritance of traits in fruit flies.
    Contribution: He discovered that the affect of crossing over creates gamete diversity.
  • Archibald Garrod

    Archibald Garrod
    Experiment: He observed inherited disease called alkaptonuria. It turns urine red. He said that the person was missing an enzyme that broke down what made the urine red
  • Frederick Griffith

    Frederick Griffith
    Experiment: He started with pathogenic and harmless bacteria. He killed the pathogenic bacteria and gave the cell remains to the living harmless cells. It turned the bacteria pathogenic.
    Contribution: He discovered there was a transforming factor the causes heritable change.
  • George Beadle and Edward Tatum

    George Beadle and Edward Tatum
    Experiment: They studied the same type of molds on the same surface. The ones that couldn't grow were lacking an enzyme and had a defective gene.
    Contribution: Genes dictate the production of specific enzymes.
  • Erwin Chargoff

    Erwin Chargoff
    Experiment: On a polynecleotide chain he discovered that A pairs went with T and that G pairs went with C
    Contribution: Adenine in DNA is equal to thymine. Guanine is equal to cytosine.
  • Alfred Hershey and Martha Chase

    Alfred Hershey and Martha Chase
    Experiment: they used radioactive isotopes in protein and 8 DNA
    Contribution: DNA was genetic material of bacteriophage T2
  • Maurice Wilkins and Rosalind Franklin

    Maurice Wilkins and Rosalind Franklin
    Experiment: They made an X-ray crysallographic photo of DNA.
    Contribution:Their picture was the first that gave the basic shape of DNA which is a double helix.
  • James Watson and Francis Crick

    James Watson and Francis Crick
    Experiment: They used wire and made a mosel following the photo from Rosalind Franklin and they used data that was already known.
    Contribution: They discovered DNA's shape was a double helix. They discovered the position of nitrogen bases. The diameter is two nm and the bases were 1/3 nm apart.
  • Marshall Nirenburg

    Marshall Nirenburg
    Experiment: He synthesized artificial RNA by linking identical RNA nucleotides.
    Contribution: He deciphered the first codon.