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    Genetics Contributions

  • Gregor Mendel

    Gregor Mendel
    He prevented self polination from pea plants. To fertalize the plant he dusted its carpel with pollen from another plant. The carpels developed into pods which turned into seeds he planted. The seeds grew into offspring plants. He discovered the laws of inheritance, and principle of independent assortment.
  • William Bateson and Reginald Punnett

    William Bateson and Reginald Punnett
    They crossed double heterozygous plants that were dominant for purple, and long pollen grains. They discovered linked genes.
  • Thomas Hunt Morgan

    Thomas Hunt Morgan
    Crossed gray body long winged fly with black body vestigial wings. The results were female red eyes, and males white eyes. He discovered crossing over, and sex linkage.
  • Archibald Garrod

    Archibald Garrod
    Hypothesized that nornal individuals have a certain enzyme that breaks down alkapton. He discovered that genes dictate phenotypes through enzymes, and individuals have enzymes that break down alkapton.
  • Fredrick Griffith

    Fredrick Griffith
    He studied two bacterias one that was harmful and one that caused diseases. He killed the pathelogic bacteria with heat and thn mixed the cell remains with living bacteria of harmless veriety and noticed some cells turned pathelogic. He discovered transformation.
  • George Beadle and Edward Tatum

    George Beadle and Edward Tatum
    They Studied a mold that was not able to grow like usual, and found out that it lacked an enzyme in a metabolic pathway that the mold needed to grow. They discovered one-gene, one-enzyme hypothesis.
  • Erwin Chargaff

    Erwin Chargaff
    The amount of adenine is equal to the amount of thymine, and the amount of guanine is equal to the amount cytosine.
  • Maurice Wilkins and Rosalind Franklin

    Maurice Wilkins and Rosalind Franklin
    They used a crystallographic to photograph DNA. They discovered the DNA helix.
  • Alfred Hershey and Martha Chase

    Alfred Hershey and Martha Chase
    Thet mixed radioactive phages with bacteria left the phages infect the bacteria. Then used a blenderagitate phages to seperate the outside and inside of bacteria cells. Then they measured the radioactivity in the pellet of liquid. Discovered injecting DNA molecules caused cells to produce more phage DNA and proteins.
  • James Watson and Francis Crick

    James Watson and Francis Crick
    They constructed the double helix with nitrogen bases in a specific order. They discovered DNA double helix and how it was set up.
  • Marshall Nirnenberg

    Marshall Nirnenberg
    They added RNA into a cell-free of ecoli, then they added DNase, which breaks apart the DNA, so that no additional proteins would be produced other than their synthetic RNA. They then added 1 radioactively labeled amino acid, the building blocks of proteins, and 19 unlabled protein radioactive genetic code of RNA for phenylaline. He translated the genetic code.