DNA Replication and Repair

Problem : How does the 3' to 5' proof-reading exonuclease work?

Problem : Where does the exonuclease cut the daughter strand to remove an improperly paired base?

Problem : What are the three main sources of DNA damage?

Problem : Thymine dimer mutations are corrected by what DNA repair system?

Problem : In the mismatch repair system, how does the exonuclease distinguish which base is the correct one?