Tutorial Molecular Facts and Figures

IDTutorial: Molecular Facts and Figures Nucleic Acids DNA/RNA bases: DNA and RNA are composed of four bases each. In DNA the four are Adenine (A), Thymidine (T), Cytosine (C), and Guanine (G). In RNA the four are Adenine (A), Uracil (U), Cytosine (C), and Guanine (G). The five nucleic acid bases have two basic structures; purine and pyrimidine. Purine: Pyrimidine: DNA and RNA sugars: Both DNA and RNA contain 5-carbon sugars (pentose sugars). In RNA the sugar is ribose and in DNA it is deoxyribose. d-ribose 2-deoxy-d-ribose ©2005 Integrated DNA Technologies. All rights reserved. 1 Nucleosides and Nucleotides: When a DNA or an RNA base is coupled with a pentose sugar the unit is called a nucleoside. When a phosphate is added to the nucleoside, it becomes a nucleotide, or nucleotide monophosphate. NH NH2 2N NN O N OO-O P OO OH H - H HOH H H H OH H OH H Cytosine nucleoside Cytosine nucleotide A DNA Strand: The correct structure of a single stand of DNA was produced by Professor P.A.T. Levene in 1935. It took almost twenty years to discover the correct structure of a ...