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DNA and the Language of Life. Chapter 11. Genes are Made of DNA. Griffin’s experiment (1928) Avery’s experiment (1944) Hershey and Chase experiment (1952). Griffith’s experiment - 1928.
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DNA and the Language of Life Chapter 11
Genes are Made of DNA • Griffin’s experiment (1928) • Avery’s experiment (1944) • Hershey and Chase experiment (1952)
Griffith showed that although a deadly strain of bacteria could be made harmless by heating it, some factor in that strain is still able to change other harmless bacteria into deadly ones. He called this the "transforming factor."
Avery’s experiment - 1944 • Transforming factor - Protein or DNA? Avery and colleagues treated a mixture of heat- treated deadly strain and harmless strain of bacteria with: • Protein-destroying enzyme • DNA-destroying enzyme
A NUCLEOTIDE has three parts: • A ring-shaped sugar called deoxyribose • A phosphate group • A nitrogenous base (single or double ring of carbon and nitrogen atoms)
Nucleotide monomers join together by covalent bonds between the sugar of one nucleotide and the phosphate of the next, forming a sugar-phosphate backbone.
The bases pair up (A-T & G-C) forming the double helix first described by Watson and Crick