MBG 1000 Lecture Notes - Lecture 5: Dna Replication, Dna Polymerase, Reading Frame

• School: University of Guelph
• Department: Molecular Biology and Genetics
• Course: MBG 1000
• Professor: Georgevander Merwe

Document Summary

Mutations: a change in the nucleotide sequence of dna, source of genetic variation, outcome can be neutral, beneficial, detrimental, origin. Induced mutations: environmental impact, ex: free radical damage (metabolism, ex: environmental impact (uv, chemical) Spontaneous mutations: changes in the nucleotide sequence as a result of errors in dna replication, dna polymerase replicated dna, native proof reading activity can correct its errors, dna repair mechanism. In bodies to recognize where damage is done to the dna: problems- function, error rate, on average, 1-12 gametes out of 1 000 000 human gametes will have a mutation in some gene. Macro scale mutations: chromosomal mutations, occurs during cell division/sexual reproduction. Involves multiple genes; often large fragments of dna: deletions- removing, duplication- doubling. Involves the substitution of one nucleotide base for another: arise spontaneously or can be induced. Insertion or deletion of nucleotides into a gene to alter the reading frame of the gene. Insertion- exchange of chromosomes: effects- different genes at same time.