BIO 370 Lecture Notes - Lecture 4: Mutation Rate, Genetic Variation, Genome Size
Document Summary
Early limitation of early ideas of evolution - poor understanding of genetics. Darwin - blending model eventually all the variation would be gone (variation is necessary for evolution to occur by natural selection. Transitions are more frequent than transversions - pt. Differences btw organisms, genes of same organism and genome size. 100 k fold variation in rates among species. Mutations are errors in replication - cells that replicated more are more likely (pre- vs post-gamete formation) Genetic variation in proteins that carry out the replication/repair, etc. Hypothesis 1: changes in the environment cause favorable mutations to appear. Hypothesis 2: mutations appear at random with respect to what the environment favors. Bacterial mutations for resistance to a virus. Start culture from a single bacterial cell grow culture to large population size plate out cells and develop into a colony add virus to the culture to kill almost all the colonies (survivors - different alleles)
