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18 Cards in this Set
- Front
- Back
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What did Friedrich Miescher discover in 1869?
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"Nuclein" - the first isolate from the nucleus, gathered from pus.
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What were the old terms for DNA and RNA?
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DNA called "thymus nucleic acid"
RNA called "yeast nucleic acid" |
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What was the "tetranucleotide hypothesis"?
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Idea that repeating units of four nucleotides have a structural role.
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What was the error in the "tetranucleotide hypothesis"?
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It stated that the 4 bases were equivalent.
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What did Frederick Griffith identify in 1928?
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He identified the "transforming principle" using mice.
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What was the setup of Frederick Griffith's experiment in 1928?
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Using mice and Streptococcus he injected nonvirulent (R) bacteria, virulent (S), heat-killed virulent (S), and a combination of (R) and heat-killed (S). When he recovered live type (S) from the combination he proved that a "transforming factor" had changed the type R into S.
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What did Astbury and Bell publish in 1938?
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Astbury and Bell published the first X-ray diffraction pattern of DNA, indicating periodicity (repeating structure).
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What did Avery, MacLeod, and McCarty first do in 1944?
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They chemically purified the "transforming principle" (DNA).
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What bias existed prior to Avery, MacLeod, and McCarty's experiments?
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The bias was that the "transforming principle" had to be protein because protein was complex.
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What did Avery, MacLeod, and McCarty add to their purified "transforming principle" to identify it?
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Proteinase (no effect), RNase (no effect), and DNase (no more transforming principle).
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What did Hershey and Chase do in 1952?
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They compared whether protein or DNA was transferred to bacteria by bacteriophage.
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How did Hershey and Chase verify that nucleic acids were transferred to bacteria by bacteriophages?
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They labeled proteins with Sulfur 35 and nucleic acids with Phosphorous 32.
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What did Erwin Chargaff do in the late 1940s?
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Devised reliable paper chromatography techniques to isolate base composition of DNA.
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What did Chargaff's experiments prove?
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The levels of adenine=thymine and the levels of cytosine=guanine in DNA.
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What did Francis Crick propose in 1958?
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The central dogma of molecular biology (DNA -> RNA -> Protein).
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What was determined in 1969?
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The entire genetic code.
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What were first constructed in 1972?
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Recombinant DNA molecules
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What technique was developed in 1986?
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Polymerase chain reaction (PCR) was developed by Kary Mullis at Cetus Corporation.
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