Bio H - DNA replication

images

intro

bonds between dna

• a = t
  • ==2== hydrogen bonds
• c = g
  • ==3== hydrogen bonds

replication

• starts at the ==origin of replication==
• ==dna helicase== = ==breaks== hydrogen bonds
• ==rna primer== = triggers process to ==start==
• ==protein stabilizers== = keeps ==dna intact== when hydrogen bonds break
• only reads ==3 → 5==
• the ==lagging== strand goes in ==fragments==
  • Okazaki fragments
• ==dna ligase== = ==bonds== the fragments together
  • think of glue
• joins together with ==old lagging + new leading== or ==new lagging + old leading==
  • semi-conservative replication

slideshow

how dna copies itself

• the process of dna can be summarized
  • enzyme helicase unwinds the first double helix
  • enzyme primase puts a short peice down of rna termed the primer
  • dna polymerase reads along each naked single strand adding teh complementary nucleotide

• dna polymerase can only build a strand of dna in one direction
  • leading strand is made continously if one primer
  • lagging strand is assembled in segments cteatedrfrom many primers
• rna primers are removed and replaced with dna
• ligase joins the ends of newly-synthesized dna
• mechanism exists for dna proofreading and repair