DNA: Strucutre and Function Flashcards
what is the function of DNA
to code for genetic information
what monomers make up the DNA polymer
nucleotides
whats the structure of DNA nucleotide
- a deoxyribose penrose sugar
- phosphate group
- nitrogenous base
what are the nitrogenous bases in DNA
adenine
thymine
cytosine
guanine
how is a polynucleotide formed
phosphodiester bonds form between the pentose sugar of one nucleotide and the phosphate group of another via condensation reactions
why is the sugar-phosphate backbone strong
there are strong covalent bonds formed between the pentose sugar and phosphate group
describe a DNA molecule
a double helix formed from two polynucleotide strands which have been bonded together with hydrogen bonding
which bonds form between the polynucleotides to form the double helix
hydrogen
what word refers to the opposing directions of the polynucleotides
anti-parallel
what does the sugar-phosphate bone refer to
the strong covalent bonds between sugar and phosphate groups which hold the polymer together
between what structure do the hydrogen bonds form to create the double helix
the nitrogenous bases
- adenine
- thymine
- cytosine
- guanine
how many hydrogen bonds form between adenine and thymine
two
how many hydrogen bonds form between cystosine and guanine
three
how does the sugar-phosphate backbone relate to the function of DNA
enables stability
how does the double strands / double helix struutre relate to its function
enables one strand to be used as a template during DNA replication
