Chapter 19 - Variation and selection in populations. This chapter involves the study of how genetic laws impact the genetic makeup of a population. Mendelian principles are the basis for the Hardy-Weinberg law which allows one to calculate allele and genotype frequencies from one generation to the next. The Hardy-Weinberg law can be used only if other forces are not acting on the allele frequency. Those forces include selection, migration, mutation, and population size. | PowerPoint to accompany Genetics: From Genes to Genomes Fourth Edition Leland H. Hartwell, Leroy Hood, Michael L. Goldberg, Ann E. Reynolds, and Lee M. Silver Prepared by Mary A. Bedell University of Georgia Copyright © The McGraw-Hill Companies, Inc. Permission required to reproduce or display Hartwell et al., 4th edition Beyond the Individual Gene and Genome PART VI Copyright © The McGraw-Hill Companies, Inc. Permission required to reproduce or display Hartwell et al., 4th edition, Chapter 19 Variation and Selection in Populations The Hardy-Weinberg Law: Predicting Genetic Variation in Populations Causes of Allele Frequency Changes Analyzing Quantitative Variation CHAPTER OUTLINE CHAPTER Three subfields of genetics based on the unit object that is the focus of study Molecular genetics – the unit entity is the gene Formal genetics – the unit entity is the individual organism, defined by genotype Population genetics – the unit entity is a population of interbreeding individuals Copyright © The McGraw-Hill Companies, Inc. Permission required to reproduce or display Hartwell et al., 4th edition, Chapter 19 Terms used to describe populations Population – group of interbreeding individuals of the same species that inhabit the same space at the same time Gene pool – sum total of alleles carried by all members of a population Changes can occur because of mutation, immigration of new individuals into or out of the population, or decreased fitness Microevolution – changes in allele frequencies within a population Copyright © The McGraw-Hill Companies, Inc. Permission required to reproduce or display Hartwell et al., 4th edition, Chapter 19 Terms used to describe populations (cont) Phenotype frequency – proportion of individuals in a population that have a particular phenotype Genotype frequency – proportion of individuals in a population that carry a particular genotype Example: A gene with two alleles (A and B) in a population of 20 | PowerPoint to accompany Genetics: From Genes to Genomes Fourth Edition Leland H. Hartwell, Leroy Hood, Michael L. Goldberg, Ann E. Reynolds, and Lee M. Silver Prepared by Mary A. Bedell University of Georgia Copyright © The McGraw-Hill Companies, Inc. Permission required to reproduce or display Hartwell et al., 4th edition Beyond the Individual Gene and Genome PART VI Copyright © The McGraw-Hill Companies, Inc. Permission required to reproduce or display Hartwell et al., 4th edition, Chapter 19 Variation and Selection in Populations The Hardy-Weinberg Law: Predicting Genetic Variation in Populations Causes of Allele Frequency Changes Analyzing Quantitative Variation CHAPTER OUTLINE CHAPTER Three subfields of genetics based on the unit object that is the focus of study Molecular genetics – the unit entity is the gene Formal genetics – the unit entity is the individual organism, defined by genotype Population genetics – the unit entity is a population of .
