BIOL 112 Chapter Notes - Chapter 4: Nucleic Acid Double Helix, Endergonic Reaction, Macromolecule

• School: UBC
• Department: Biology
• Course: BIOL 112
• Professor: Karen Smith

Document Summary

Nucleic acids: - polymers made of nucleotides instead of amino acid monomers like proteins. A sugar: organic compound with a carboxyl group and several oh- groups. Two kinds of sugars: ribose (oh on 2") A nitrogenous base: attached at 1" of sugar. Phosphodiester linkage: rxns = bond between phosphate group of one nucleotide and the hydroxyl group on the sugar of another nucleotide. If the sugar is ribose = rna, deoxyribose (always 5" 3") Process needs energy, free energy of nucleotide monomers add 2 phosphate groups to ribonucleotides or deoxynucleotides = triphosphates = phosphorylated. * adding of 1+ phosphates = increase pe of substrate molecule = endergonic rxn. Sugar phosphate backbone created by phosphodiester linkages, 4 nitrogenous bases extending out. Double helix due to antiparallel strands (one runs 5" 3" and one 3" 5") Complementary base pairing: purines with pyrimidines, a-t (u in rna) c-g. Template strand: strand of dna transcribed by rna polymerase to make complementary rna/dna.