Erwin Chargaff's work on the composition of nucleic acids began in 1944. His findings, which later became known as Chargaff's rules, detail the specific pairings that occur in double-stranded DNA molecules. According to one of Chargaff's rules, a section of DNA molecule that contains 50 base pairs and has 15 adenine bases must also contain: A) 15 guanine bases B) 15 cytosine bases C) 15 thymine bases D) 15 uracil bases
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So, if a section of DNA molecule contains 15 adenine bases, it must also contain 15 thymine bases (since A=T). This means that out of the 50 base pairs in the section, 30 of them are accounted for (15 A and 15 T). According to Chargaff's rule, the remaining Show more…
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Biochemist Erwin Chargaff was the first to discover that, in DNA, [A] = [T] and [G] = [C]. These equalities are now known as Chargaff's rule. Using Chargaff's rule, determine the percentages of all of the bases in DNA that is 22% thymine. Adenine = Cytosine = Guanine =
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Erwin Chargaff investigated the nucleotide composition of DNA. He analyzed DNA from various organisms and measured the relative amounts of adenine (A), guanine (G), cytosine (C), and thymine (T) present in the DNA of each organism. The table below contains a selected incomplete data set of his results. Source of DNA Adenine Guanine Cytosine Thymine Sea urchin 32.8% 17.7% 17.3% 32.1% Salmon 29.7% 20.8% 20.4% 29.1% Wheat 21.8% 22.6% E. coli 24.7% 26.0% Human 30.4% 30.2% Ox 29.0%
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