MBG 2040 Study Guide - Final Guide: Acridine, Mutagen, Enol
14 Dec 2015
School
Department
Course
Professor
Document Summary
Mutagen: physical and chemical agents that cause changes in. Dna, such as ionizing irradiation, uv light or certain chemicals source of all genetic variation. Nonsense: premature termination (results in stop codon) Missense: amino acid change, impaired function frameshift: insertion/deletion that disrupts translation reading frame transition: replaces pyrimidine/pyrimidine or purine/purine transversion: replaces pyrimidine/purine or purine/pyrimidine. Alkylating agents- add methyl, ethyl, etc. groups. Nitrous acid- remove amino group: oxidative deamination, transition mutation. Acridine dyes: intercalate between bases: framseshift mutation. Uv irradiation: crosslinking of adjacent t forms thymine dimers which block replication and activate repair mechanisms. Ionizaing: breaks chromosomes and causes deletions, duplications, inversions and translocations. Dna repair endonuclease/ endonuclease-containing complex recognizes, binds to, and excises the damaged base. Dna polymerase fills in the gap, using undamaged complementary strand of dna as template. Dna ligase seals break: mismatch repair. Aids in removal of incorrect bases during replication. Muts recognizes mismatches and binds to them.
