Dna structure

DNA through history

  • Gregor Mendel (1822-1884), the father of genetics

    Gregor Mendel (1822-1884), the father of genetics
    Gregor medel was a monk that using pea plants discovered the fundamental inheritance laws. He observed or deduced by many experiments that genes come in pairs and that one of each them comes from one parent. He tracked genes and discovered that one gene was recessive and the other dominant.
  • Friederich Miescher (1844-1895), the isolation of DNA

    Friederich Miescher (1844-1895), the isolation of DNA
    He was interested on chemistry of cells. He went to hospitals and took evyrthing that had pus, and put a weak alkaline solution to the white blood cells, cells lysed and he observed the nuclei of them went to the bottom. He added "nuclein" to them and proved that nuclein worked as a storehouse because of the amount of phosphorous. He develop this experiment and allowed the study of clear biological studies for nuclein and prepared the path to know how the hereditary carriors work.
  • Hugo De Vries (1848-1935), Hybridization experiments

    Hugo De Vries (1848-1935), Hybridization experiments
    Vries was a netherlander profesor of botany that without knowing Mendel's laws made hybridazation experiments and got the same conlutions as Mendel. With the help of Correns and Tschermak tried to publish the rediscoveries but by right problems was imposible.
  • Erich Von Tschermak (1871-1962)

    Erich Von Tschermak (1871-1962)
    He was a botany that made pea plants breeding experiments, and by 1900 he wrote with the help of Vries and Correns the "Mendelian" laws of inheritance. He also produced high-yielding food crops and became one of the major influence in agricultural and plant breeding in Austria, his home.
  • Carl Erich Correans (1864-1933), Redescovering Mendel's laws

    Carl Erich Correans (1864-1933), Redescovering Mendel's laws
    Carl was a botany that mostly redefined Mendel's inheritance laws. All thought he made big discoveries, he had a association with Tschermak and Vries, and because of problems of rights and by the bomb in Berlin during 1945, almost most of its discoveries got lost.
  • Thomas Hunt Morgan (1866-18945), theory of inheritance

    Thomas Hunt Morgan (1866-18945), theory of inheritance
    This amercan was the one that in 1911 established the chromosomal theory of inheritance and by the Drosophila or Friut fly, commonly knowned, analized de evolution of species during tme. He developed ideas and prooved the chromosomal theory of heredity, genetic linkage, chromosomal crossing over and non-disjunction. He is also known because of the use he gaved t the ''new'' equipment as a binocular microscope his friend Calvin Bridge introduced.
  • Herman Muller (1890-1967), X-rays induce mutations

    Herman Muller (1890-1967), X-rays induce mutations
    Herman Muller was an american that studied on thomas morgan's drosophila lab, and by this experiments he prooved that the mutation of a gene can alter the impression of another gene. With this discover by 1920 he won a nobel price of researching showing that X-rays could induce mutations. With his fame he alerted doctors that Xrays were bad if they were use in a indiscriminate way.
  • Barbara Mcclintock (1902-1992), pioneer in plant genetics

    Barbara Mcclintock (1902-1992), pioneer in plant genetics
    This aerican womas was the pioneer in developing a work in plant genetics and in the mechanisism of transposition in corn. She imporved a method that was able to identify maize chromosomes. The next step of her investigation was to focous in corn chromosomes in the investigation of Morgan's group of the chromosome's linkage. She analized that with the use of x rays in corn's chromosomes, developed transloations, inversions, deletions and ring chromosomes in corn. In 1983 she won a Nobel prize.
  • George Wells Beadle (1903-1989),"one gene, one protein"

    George Wells Beadle (1903-1989),"one gene, one protein"
    The american graduated of Agriculture with some degree of science, He was part of the Emerson's group as Barbara Mcclintock also, and they discovered the number of the chromosomes of the Neurospora. He applied it in Morgan's lab and published papers of crossing over and developed the technique of imagianl disc transplantations. George determine that drosophila's genes determine its eye color so put as a hypothesis "one gene, one protein". He shared with tatum the nobel price in 1958.
  • Joshua Lederberg (1925)

    Joshua Lederberg (1925)
    When he was very little, he became interested in Beadle's and Tatum's experiment of Neurospora. He later worked in a clinical parasitology lab of the U.S Naval Hospital, he did not see active service, so returned to Ryan's lab and published a paper that contained the transforming ability of DNA. Later he made experiments of the Neurospora using bacteria allthought they were not proved yet that had genes, and by experiments he proved that bacterial conjugation occured.
  • Oswald Theodore Avery (1877- 1955)

    Oswald Theodore Avery (1877- 1955)
    Showed with Maclyn Mcarty the "transforming principle"of DNA. He worked with bacteria applying different innmunological and chemical methods and publish a study of tuberculosis bacterium. Oswald also proved the transforming factor as in pneumonia.
  • Evelyn Witkin (1921)

    Evelyn Witkin (1921)
    She showed how certain hereditary features can change because of the external or enviromental factors. She was involved on the studies of DNA mutagenesis and the nature of DNA, and also proved how the UV rays affects the DNA.
  • Erwin Chargaff

    Erwin Chargaff
    He was a biochimist. Discovered that the amount of adenine was always equal to the amount of thymine in DNA. And the amount in DNA of guanine is always equal to the cytosine. It helped understand the DNA structure
  • Rosalind Franklin

    Rosalind Franklin
    The britain scientist and chemist Rosalind Franklin was the pioneer in making images of the DNA molecules by a process knowned as X-ray diffraction. Their images suggested the DNA had a spiral shape.
  • Linus Pauling

    Linus Pauling
    He exposed that the structure of DNA was a tripel-standed helix structure. And proposed that the bases of the 'ladder'' was made by phosphate and sugars ans that the ''steps'' were made by Adenine, Thymine, Cytosine and Guanine.
  • Watson and Crick's Model

    Watson and Crick's Model
    after wconcluded than DNA structure were long and as a twisted ladder. They built a model with simple materials from their lab, and it perfectly fits with other scientists findings.
  • Zamenick and Hoagland descoveries

    Zamenick and Hoagland descoveries
    After questions without answers related to amino-acids and proteins, both showed that aminoacids are activated by ATP before they are incorporated to peptide chain. both develop also anti-sense blockers.
  • Franklin Stahl and Mathew Meselson experiment

    Franklin Stahl and Mathew Meselson experiment
    developed the technique of density gradient centrifugation and used it to prove that DNA was replicated in a semi-conservative way, as predicted by Watson and Crick in their 1953 paper. And Franklin's current investigation is based on mechanisims of genetic combination.
  • Arthur Kornberg (1918)

    Arthur Kornberg (1918)
    he isolated DNA polymerase I and show that life (DNA) can be made in a test tube. He won a nobel price in 1959 for the enzymatic synthesis of DNA
  • Roy John Britten (1919)

    Roy John Britten (1919)
    Roy Britten showed that eukaryotic genomes have many repetitive, noncoding DNA sequences.
  • David Baltimore and Howard Tenim´s experiment

    David Baltimore and Howard Tenim´s experiment
    Franklin had experimental evidence that showed how certain viruses seem to shut down synthesis of cellular RNA and induce synthesis of viral RNA about Howard Temin's DNA provirus hypothesis that viral RNA was a template to make viral DNA, which then became the template for the synthesis of progeny viral RNA.
  • Roberts and Sharp's RNA splicing

    Both developed or introduced us a enzyme called restriction endonucleases, and the show this by experiments of cutting and analyzing DNA. It gave as a result that every little cut has a DNA sequence.
  • Fred Sanger and DNA sequencing

    Fred Sanger and DNA sequencing
    He was the first to determine the sequence of amino acids in a protein, that 51 amino acids of the insuline protein arrenge in a specific order. In the 1975 he developed a method to determine the exact sequence of nucleotides on a gene.
  • Leland Hartwell (1939)

    Hartwell was a pioneer in the use of yeast as an experiment, he needed to use something easy to show cell's growth. Pioneer in yeast genetics and to find out the cell's cycle.
  • Howard Robert Horwitz (1947)

    is an American biologist best known for his research on the nematode worm . By this studies he exhibit that by the study of this worm, we can see the fast development of neurons and the genetics of the cell's linage.
  • Mary Claire King (1946)

    Mary Claire King (1946)
    She revolutionize the ebiological evolution with prooves that chimpanzees and humans shared the 99% of their genetic material. She is specialized on recording familie's cancer history and had her own goal to find the responsable gene for breast cancer.
  • Patrick Henry Brown (1954)

    He showed that the "genetic differences"are made by the sequences in DNA.