nucleic acid Flashcards
elements in nucleic acids?
C H O N & P
“nucleic acids” definition
large polymers formed from many nucleotides (monomers)
nucleotide components?
- pentose monosaccharide
- phosphate group PO4 2-
- nitrogenous base
“pentose monosaccharide”
monosaccharide containing 5 carbon atoms
“phosphate group”
inorganic molecule that’s acidic and negatively charged
“nitrogenous base”
complex organic molecules contains 1 / 2 carbon rings + nitrogen in structure
nucleotides reaction?
condensation reaction of nucleotides —> polynucleotide
phosphate group at C5 of pentose sugar forms covalent bonds with hydroxyl group of C3 adjacent nucleotide’s pentose sugar
where do the bonds form between nucleotides?
phosphate group at C5 of pentose sugar forms phosphodiester bonds with hydroxyl group at C3 of adjacent pentose sugar
phosphodiester bonds
how are the bonds between nucleotides broken?
phosphodiester bonds broken by hydrolysis
“deoxyribose”
sugar with one less oxygen atom that ribose
DNA bases:
A T C G
“pyramidines”
smaller bases with single carbon ring structures
which bases are pyramidine?
T & C
(inside of AT CG ; smaller = protected)
“purine”
larger bases with double carbon ring structures
which bases are purine?
A & G
*(outside of AT CG ; bigger = protecting) *
what is the DNA double helix?
2 strands of polynucleotides coiled into a helix
what are the bonds between the double helixes?
hydrogen bonds between complementary bases
what does each strand have?
- phosphate group ‘5 end
- hydroxyl group ‘3 end
antiparallel
double helix strand arrangement?
antiparallel strands = strand reading forwards on one with read identically from the opposite side on the other
number of bonds between A & T?
2 hydrogen bonds
number of bonds between C & G?
3 hydrogen bonds
why are pyramidine purine arrangements necessary?
smaller pyramidine always binds to larger purine = maintains constant distance between DNA backbone = parallel polynucleotide chains
what does complementary base pairing mean for DNA?
same number of A & T and same number of C & G
