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6.1 DNA and the Code of Life. Pages 228-233. nuclein. A name given to DNA when it was discovered by Friedrich Miescher in 1869. Joachim Hammerling. performed experiments on Acetabularia to verify that the genetic material was in the nucleus .
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6.1 DNA and the Code of Life Pages 228-233
nuclein • A name given to DNA when it was discovered by Friedrich Miescher in 1869.
Joachim Hammerling performed experiments on Acetabularia to verify that the genetic material was in the nucleus. image: taringa.net image: biologysemester58.wikispaces.com
Alfred Hershey and Martha Chase 1952- showed that viruses needed only to inject their DNA into a bacteria to produce more viruses. Image: osulibrary.orst.edu
Phoebus Levene 1920’s DNA was composed of: • A pentose sugar (cyclic, 5-carbon sugar) • A nitogenous base • A phospate group, PO43-
5 Carbon sugar • Deoxyribose has one less oxygen atom than ribose. Image: mun.ca
Phosphate group PO43- image: m2c3.com
Nitrogenous Bases • Adenine, guanine, cytosine, thymine Image: faculty.ccbcmd.edu
Erwin Chargaff 1940 The amount of Adenine, A, is equal to the amount of Thymine, T. The amount of Guanine, G, is equal to the amount of Cytosine, C.
Nucleotide • DNA has a negative charge because of the phosphate ions in its backbone. image: dnareplication.info
Rosalin Franklin 1951 X-ray crystallography: x-rays were aimed at a crystal of DNA to produce a diffraction pattern. Image: cwp.library.ucla.edu image: shellemsbioblog.blogspot.com
James Watson and Francis Crick • 1953 DNA model Image: chemheritage.org
Complimentary base pairing Image: dedunn.edublogs.org