nucleic acids and chromosomes Flashcards
nucleic acid structure: explain the structure of DNA and RNA, list the bases found in DNA and RNA and indicate which ones are purines and which ones are pyrimidines (9 cards)
nucleotide and nucleoside
nucleotide: 1 (or more) phosphate on C5; deoxyribose sugar; nitrogenous base on C1 (B-glycosidic link); nucleoside: no phosphate group on C5
DNA structure
double stranded; deoxyribose sugar; phosphate on C5; nitrogenous base on C1 (B-glycosidic link)
RNA structure
single stranded; oxyribose sugar; phosphate on C5; nitrogenous base on C1 (B-glycosidic link)
DNA purines
A, G; 2 rings
DNA pyrimidines
T, C; 1 ring
RNA purines
A, G; 2 rings
RNA pyrimidines
U, C; 1 ring
primary structure of DNA chain
linear polymer of nucleotides; primary: 3’OH → PO4 2- → 5’OH (adjacent) so asymmetrical 3’ and 5’ ends; written from 5’ (free phosphate) to 3’ (free OH)
secondary structure of DNA helix
minor and major grooves; right-handed double helix; antiparallel strands; -ve PO4 2- on outside (3’ to 5’ and 5’ to 3’); base stacking increases stability; flat base plane perpendicular to helix
