Define proof-reading. What activity of DNA polymerase provides function? Next, define mis-incorporation rate vs. error rate and how they relate proof-reading and mutation rate. Describe 2 circumstances when high fidelity replication is a disadvantage (i.e. when error- prone replication is advantageous).
Answer =
proof-reading =
The mechanisms that correct errors during DNA replication and to repair DNA damage over the cells lifetimeis called as proofreading.
activity of DNA polymerase that provides this function is= the 3' to 5'proof reading exonuclease activity of DNA polymerase.
the 3' to 5'proof reading exonuclease works by scanning along directly behind as the dNA polymerase adds new nucleotides to the growing strand.
If the last nucleotide is mismatched ,then entire replication holoenzyme backs up & removes the lastincorrect base.
& attempt to add the correct base again.
Define proof-reading. What activity of DNA polymerase provides function? Next, define mis-incorporation rate vs. error rate...
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