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      <title>DNA timeline by A&#39;lexia Lumpkin</title>
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      <pubDate>2023-02-22 15:24:16 UTC</pubDate>
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         <title>Frederick Griffith-1928 </title>
         <author>al14982</author>
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         <description><![CDATA[<ul><li>Frederick Griffith was a British bacteriologist who experimented with bacterium and discovered that DNA is the carrier of genetic information, which is now named the "Griffith experiment." He studied the epidemiology and pathology of bacterial pneumonia. Griffith combined living non-virulent bacteria with a heat-inactivated virulent form in this experiment. Griffith also discovered the difference between the S and R strains of bacteria, which is the S strain is the "virulent" strain capable of causing death in mice and the R strain is the "nonvirulent" strain that will not cause death in mice. Fredericks's main focus was the possibility of developing a pneumonia vaccine for those who were sick. This taught him and another scientist that some chemicals transferred from the dead virulent cells into the avirulent cells and changed them. Griffith had a big impact on scientists and his information was passed down to others after succeeding.<br><br></li></ul>]]></description>
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         <pubDate>2023-02-22 16:05:00 UTC</pubDate>
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         <title>Oswald Avery- 1944</title>
         <author>al14982</author>
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         <description><![CDATA[<div>Oswald Avery was an American bacteriologist who made his discovery in 1944. His discovery was that DNA is the substance responsible for heredity. While Avery worked with other scientists named <a href="https://www.britannica.com/biography/Maclyn-McCarty">Maclyn McCarty</a> and Colin MacLeod. His work also helped to understand the c<a href="https://www.britannica.com/science/chemistry">hemistry</a> of <a href="https://www.britannica.com/science/immunity-biology">immunological processes</a>. Avery and colleagues found a substance in the blood and urine of an infected person that was produced by this bacterium. They identified the substance as a complex carbohydrate called a polysaccharide. Avery also found that the polysaccharide could stimulate an immune response and that the bacterium influences virulence.</div>]]></description>
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         <pubDate>2023-02-22 17:55:57 UTC</pubDate>
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         <title>Erwin Chargaff-1950</title>
         <author>al14982</author>
         <link>https://padlet.com/al14982/3o6y373o2z62qjce/wish/2491538996</link>
         <description><![CDATA[<div>Erwin Chargaff's research into DNA's structure paved the way for our current understanding of DNA's nature. He noticed that DNA varies between species, which made it highly credible as genetic material. His identification of ratios in DNA's bases allowed these bases to fit into the double helix and how DNA can be used to create copies of itself. Chargaff was aware of research carried out by Oswald Avery, who showed that DNA was composed of nucleotides. Chargaff believed Avery's experiment indicated that living species differed because of differences in their DNA. Erwin Chargaff found the ratios of adenine to thymine and guanine in DNA.</div>]]></description>
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         <pubDate>2023-02-22 18:08:48 UTC</pubDate>
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         <title>Alfred Hershey and Martha Chase-1952</title>
         <author>al14982</author>
         <link>https://padlet.com/al14982/3o6y373o2z62qjce/wish/2491557452</link>
         <description><![CDATA[<div>theories opposed the idea that genetic material was composed of proteins. Hershey and Chase's experiments were not the first to test this theory. Alfred Hershey studied viruses at the Carnegie Institution of Washington and later found that phages infected bacteria. Hershey and Chase analyzed what happened when phages infect bacteria and they found out that when phages infect a host bacterium, the phages first attach themselves to the outside of the bacterium.&nbsp; Hershey and Chase utilized a technique called radioactive isotope labelling and The first Hershey-Chase experiment aimed to confirm previous experimental findings that the DNA and protein components of phages were separable. Hershey and Chase also tested if enzymes, molecules that facilitate chemical reactions in cells, could degrade DNA.</div>]]></description>
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         <pubDate>2023-02-22 18:19:43 UTC</pubDate>
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         <title>James Watson and Francis crick- march 1953</title>
         <author>al14982</author>
         <link>https://padlet.com/al14982/3o6y373o2z62qjce/wish/2491573300</link>
         <description><![CDATA[<div>The Discovery of the double helix in 1953 by James Watson and Francis Crick showed how genes control chemical processes within cells. Crick and Watson recognized, early in their careers, that gaining a detailed knowledge of the three-dimensional configuration of the gene was the central problem in molecular biology. According to their findings, DNA replicated itself by separating into individual strands, each of which became the template for a new double helix. They used <strong>X-ray crystallography</strong> to identify their experiment.&nbsp; Each pair of bases lies flat, forming a "rung" on the ladder of the DNA molecule. Base pairs aren't made up of just any combination of bases.</div>]]></description>
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         <pubDate>2023-02-22 18:33:01 UTC</pubDate>
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         <title>Rosalind franklin- 1953</title>
         <author>al14982</author>
         <link>https://padlet.com/al14982/3o6y373o2z62qjce/wish/2491587277</link>
         <description><![CDATA[<div>Rosalind Franklin was a British chemist who was also a biophysicist. Franklin discovered that the<strong> structure of DNA in 1953 was X-ray diffraction</strong>. She created the famous Photo 51 which demonstrated the double helix of deoxyribonucleic acid. This also proved that the molecule contains the genetic instructions for the development of all living organisms. The discovery was unlocking the mystery of how life is passed down from generation to generation. She also had many other accomplishments but dealt with <strong>discrimination and sexism and this was a challenge to her. </strong></div>]]></description>
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         <pubDate>2023-02-22 18:44:10 UTC</pubDate>
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