Deoxyribonucleic acid molecular model

DMF, see Dimethylformamide DM SO, see Dimethyl sulfoxide DMT (dimethoxytrilyl ether), DNA synthesis and, 1114 DNA, see Deoxyribonucleic acid DNA fingerprinting, 1118-1119 reliability of, 1119 STR loci and, 1118 Dopamine, molecular model of. 930 Double bond, electronic structure of, 16... 

Ti values may occur with such native biopolymers as ribonuclease A, deoxyribonucleic acid, and collagen, whose molecular motions are restricted, but, as yet, high values have not been observed for polysaccharides in solution, or for gels, in which these motional-restriction effects may be equivalent, or less marked. However, an extensive relaxation-study by Levy and coworkers68 on poly(n-alkyl methacrylates) may serve as a model for future experiments on polysaccharides, as this type of molecule has a main chain and side chains, albeit more mobile than those in polysaccharides. 

Cytosine, a constituent of deoxyribonucleic acid (DNA) can be represented by the molecular model at the top of the next column. If 0.001 mol of cytosine is submitted to combustion analysis, how many moles of CO2 and how many moles of H2O would be formed ... 

James D. Watson (1928-) and Francis H. C. Crick (1916- ) publish two landmark papers in the journal Nature. The papers are entitled Molecular structure of nucleic acids a structure for deoxyribose nucleic acid and Genetic implications of the structure of deoxyribonucleic acid. Watson and Crick propose a double helical model for DNA and call attention to the genetic implications of their model. Their model is based, in part, on the x-ray crystallographic work of Rosalind Franklin (1920-1958) and the biochemical work of Erwin Chargaff (1905- ). Their model explains how the genetic material is transmitted. 

The following molecular models are representations of (a) adenine and (b) cytosine, constituents of DNA (deoxyribonucleic acid). Indicate the positions of multiple bonds and lone pairs for both, and draw skeletal structures (gray = C, red = O, blue = N, ivory = H). 

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