BIOL 1107 Chapter Notes -Pyrimidine Dimer, Proofreading, Base Pair
Document Summary
Understand the 3 types of errors that can occur during dna replication. Be able to define base-pair mutation and to describe the 3 types. Proofreading ~ a mechanism for correcting errors made by dna polymerase during replication. Mismatch repair ~ a mechanism for correcting errors made during replication that escape proofreading. Excision repair ~ mechanisms for correcting various kinds of dna damage, such as those caused by chemicals and radiation. Base-pair mismatches ~ the new inserted nucleotide has a base that is the incorrect one to pair with the base of the nucleotide on the template strand. Mismatch repair ~ a mechanism that corrects about 99% of the errors in nucleotide copies, which then results in an extremely high replication accuracy. Base-excision repair ~ a mechanism that corrects no bulky damage to bases by removing the erroneous base and replacing it with the correct one complementary to the base on the other.
