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Lecture 5

Directional Selection one extreme phenotype is most fit (decreases variation and changes population mean
Stabilizing Selection intermediate phenotypes most fit (decreases variation and no change in population mean)
Destabilizing Selection two extreme phenotypes are more fit than intermediate phenotypes (no change in population mean and increases variation)
Frequency-dependent Selection Fitness of phenotype depends on phenotype frequencies in the population; (a) Negative frequency dependence: fitness decreases with frequency and (b) Positive frequency dependence: fitness increases with frequency
Probability How likely is it that something will happen? The formal study of the laws of chance
Gene the functional unit of heredity
Allele alternative forms of a gene (A1 or A2, A or a, p or q) * there are two inherited alleles for each gene of a diploid organism – one maternal and one paternal
Locus/loci location of a gene on a chromosome
Homozygous refers to having identical alleles for a single trait
Heterozygous they are different from one another
Equilibrium The condition in which all acting influences are balanced or canceled by equal opposing forces, resulting in a stable system
Created by: stacymdez