ARCH 131 Lecture Notes - Lecture 3: Allele Frequency, Antimicrobial Resistance, Genotype Frequency

• School: Simon Fraser University
• Department: Archaeology
• Course: ARCH 131
• Professor: Bess Doyle

Document Summary

Mendelian traits are discrete: coded by one gene. Distribution of abo phenotypes (a monogenic trait) in a population. Polygenic traits are determined by more than one gene. Distribution of stature (height) in a population. Note that the distribution is continuous (smooth), not discrete (separate) A and b genes work together to produce phenotype. Different b alleles (b1 and b2) produce very different outcomes the phenotype is polymorphic. Lots of variation, no clear division by type . Skin colour is determined by size and ratio of 2 kinds of pigment particles: Each individual lives without evolving variation = multiple alleles. Frame shift : insertion or deletion of one or more nucleotides. Chromosomal mutation: rearrangement of large sections of dna. Remember: recombination also shuffles alleles between homologues. Most that affect phenotype are deleterious & selected out. A population is made up of organisms who can interbreed. Think of it as a mass of alleles. Mutation: new change in the genetic code.