Biology 30 - Population Genetics

Flashcards for vocabulary review.

Hardy-Weinberg Principle

A mathematical relationship that shows that allele frequencies will not change from generation to generation, as long as certain conditions are met.

Genetic Drift

When a population is small, chance fluctuations will cause changes in allele frequencies.

Founder Effect

Genetic drift that occurs if only a few individuals leave to establish a new population.

Bottleneck Effect

A serve environmental event results in a drastic reduction in population size.

Mutation

Mutations are random, and cause the gene pool to alter or the allele frequency to alter with the introduction of a new allele

Sexual Dimorphism

A striking difference between the male and female.

p

dominant allele (A)

q

recessive allele (a)

Microevolution

Evolution at a small scale, within a single population

Macroevolution

Evolution at a large scale, often leading to the formation of new species

Gene Pool

The sum total of all the genes in a given population.

Genotype Frequency

The proportion of a population with a particular genotype.

Allele Frequency

The proportion of a specific allele within a population.

Population

A group of organisms of the same species living in the same area.

Community

An assemblage of different populations living and interacting in the same area.

Ecosystem

A community of living organisms interacting with their physical environment.

Interspecific Competition

Competition between different species for the same resources.

Mimicry

When one species evolves to resemble another species.

Parasitism

Symbiotic relationship in which one organism benefits (parasite) and the other is harmed (host).

Mutualism

Symbiotic relationship in which both organisms benefit.

Commensalism

Symbiotic relationship in which one species benefits and the other is unaffected.

Climax Community

The final stable community in ecological succession.

Primary Succession

Succession in an area where there was no previous vegetation.

Secondary Succession

Succession in an area that was previously covered by vegetation.

Population Density

The number of individuals of a species in an area or volume.

Ntality

Births

Mortality

Deaths

Immigration

Movement of individuals into a population.

Emigration

Movement of individuals out of a population.

Growth Rate

The change in population size over a specific period.

Per Capita Growth Rate

How fast a population is growing compared to original population.

Open Populations

Influenced by natality, immigration, mortality and emigration

Closed Populations

No immigration and emigration; only natality and mortality determine population growth.

Biotic Potential

The maximum number of individuals that can be produced by a species under ideal conditions.

Limiting Factors

Factors that prevent populations from achieving biotic potential.

Carrying Capacity

The mximum number of individuals a habitat can sustain.

K-selected Species

Species who live in stable environments and tend to be larger in size and have few offspring

r-selected Species

Species whose populations are governed by their biotic potential (reproductive capacity, r)