Chapter 4-5 Study Guide Flashcards
Consangueneous Mating
The mating of individuals who share a biological ancestor; literal: of the same blood
Genotype Frequency
The number of individuals with a given genotype divided by the total number of individuals in the population
Gene Flow
The movement of people between areas that are already occupied may serve to introduce new alleles into a population or change allele frequencies
Point Mutation
A changeg at a particular point on the DNA molecule; Chromosomal aberrations are changes in the numer or structure of chromosomes
Assortive Mating
A preference for or avoidance of certain people for physical and social reasons
Genetic Drift
A form of Sampling Error; The situation in a small population where the allelic frequencies of the F1 generation will differ from those of the parental generation due to sampling error. A chance deviation in the frequency of alleles if the pool is too small and the number of matings are low.
Population Bottlenecking
A form of Sampling Error; This happens when a population is reduced to a small size for some reason, such as a natural disaster, causing a reduction in variation within the decending population compared to the original population.
Reproductive Isolation
A mechanism that prevents reproduction from occuring between two populations.
Examples include geographical barriers such as a river or mountain range.
Hardy-Weinberg Equilibrium
A mathematical model of genetic equilibrium:
p(squared) + 2pq + q(squared) = 1
Founder Principle (aka Founder Effect)
A form of Sampling Error; Situation in which a founding population does not represent a random sample of the original population; This may occur when a segment of a population migrates to another area.
Directional Selection
A type of natural selection characterized by a generation-after-generation shift in a population in a specific direction, such as toward larger body size.
Stabilizing Selection
A type of natural selection characterized by a generation-after-generation shift in a population in the direction of the average (mean) individual, such as average body size.
Disruptive Selection
A type of natural selection characterized by a generation-after-generation shift in the population away from the average individual, such as both larger and smaller body size.
Generalized Species
One that occupies a relatively boad ecological niche, that is, it is able to survive under a wide variety of environmental conditions.
Specialized Species
One that occupies a relatively narrow ecological niche, that is, it is able to survive only under a relatively narrow set of environmental conditions.
