Genetics Timeline

Timeline created by Abesh22
  • Gregor Mendel

    Gregor Mendel
    Experiment:
    Wanted to cross fertilize pea plants
    1.First removed stamens from purple flower
    2.Transfered pollen from stamens of white flower to the carpel of the purple flower
    3.Pollinated carpel mature into pod
    4.Planted seeds from pod
    Contribution:
    Discovered different alleles, two genes from each parent, allele pairs seperate during meiosis, one allel fully expressed the other no noticable effect
  • William Bateson and Reginald Punnett

    William Bateson and Reginald Punnett
    Experiment:
    They crossed doubly heterozygous plants that exhibited the dominant traits purple flowers and long pollen grains. the corresponding rececessive traits are red flowers and round pollen.
    Contribution:
    Discovered linked genes
  • Thomas Hunt Morgan

    Thomas Hunt Morgan
    Experiment:
    A cross between a wild type fruit fly (gray body long wings) and a fly with a black body and underdeveloped or vestigial wings
    Contribution:
    Discovere crossing over genetic recombination
  • Archibald Garrod

    Archibald Garrod
    Experiment:
    Observed that people with alkapotonuria congential disorder, when exposed to air patients urine would turn dark red
    Contribution:
    Discovered that inherited disease reflects a persons inability to make a perticular enzyme
  • frederick Griffith

    frederick Griffith
    Experiment:
    Used mice to determine which bacteria would kill them
    Contribution:
    Discovered transformation
  • George Beadle and Edward Tatum

    George Beadle and Edward Tatum
    Experiment:
    Used orange bread mold unable to grow on the usual simple groth medium
    Contribution:
    One gene one enzyme function of an original gene is to dictate the production of a single enzyme
  • Erwin Chargaff

    Erwin Chargaff
    Experiment:
    Noticed a pattern in the model, he took samples of different DNA cells to find out that (A=T) and (C=G)
    Contribution:
    Discovered that the amount of Adenine is equal to the amount of thymine, and that the amount of cytosine is equal to the amount of guanine (base pairing rules)
  • Alfred Hershey and Martha Chase

    Alfred Hershey and Martha Chase
    Experiment:
    Used bacteriophage composed only of DNA and protien, DNA tagged by radioactive phosphorus, protien was tagged with radioactive sulfur
    Contribution:
    Determined that DNA was a genetic material
  • Maurice Wilkins and Rosalind Franklin

    Maurice Wilkins and Rosalind Franklin
    Experiment:
    Took an x-ray crystallographic photograph and DNA
    Contribution:
    DNA was a helix
  • James Watson and Francis Crick

    James Watson and Francis Crick
    Experiement:
    Tried putting the back bones on the outside and forcing the nitrogren bases to swivel to the interior of the molcule (Wire Modle)
    Contribution:
    Determined that DNA was a double helix made of two Polynucleotide strands
  • Marshall Nireberg

    Marshall Nireberg
    Experiment:
    Set up a "cell free" system with "sap" from E.Coli cells containing enzymes and an energy system added simple chains of RNA with amino acids
    Contribution:
    Discovered first "Triplet" sequence of three bases of DNA codes for one of the 20 amino acids that serve as the building blocks of protien.