1.  A llele frequencies will remain constant unless one or more factors cause the frequencies to change.  If there is no change, there is no evolving.

2.  Natural selection acts on the range of phenotypes in a population.  Evolution occurs as a population’s genes and their frequencies change over time.

3.  All of the alleles of a population’s genes together make up a gene pool.  Allele frequency - % of any specific allele in the gene pool.  Genetic equilibrium – a population in which the frequency of alleles remains the same over generations.

4.  Mutations are one cause of genetic change.  Lethal mutations disappear quickly, but mutations that cause a useful variation become part of the gene pool

5.  Genetic drift – the alteration of allele frequencies by chance events.  Gene flow – transport of genes into or out of a population by migrating individuals.  Genetic drift, gene flow, and mutations can greatly affect small populations.  Natural selection is usually the most significant cause of changes in any gene pool.

6.  Some variations increase or decrease an organism’s chance of survival in an environment.  Variations are controlled by alleles.  Allelic frequencies in a gene pool will change due to natural selection of variations.

7.  If conditions are not met the genetic equilibrium is disrupted – *population evolves and changes*  If conditions are met the genetic equilibrium stays the same– *population does not evolve*

8.  Genotype proportions remain constant – calculated from allele frequencies = 1 or 100 percent P+Q = 1 or 100 percent (allele frequencies) 2 + 1 or 100 percent P 2 + 2PQ + Q 2 = 1 or 100 percent (genotype frequencies)

9.  P = frequency of the dominant allele in the population  Q = frequency of the recessive allele in the population  P 2 = percentage of homozygous dominant individuals  Q 2 = percentage of homozygous recessive individuals  2PQ = percentage of heterozygous individuals

10.  If 98 out of 200 individuals in a population express the recessive phenotype, what percent of the population are homozygous dominant?