Population Genetics

These flashcards cover key concepts and terminology essential for understanding population genetics.

Population

A group of organisms of the same species in the same geographic area that can interbreed.

Population Genetics

The study of genetic composition of populations and how it changes over time.

Polymorphism

The occurrence of two or more different forms (alleles) at a gene locus within a population.

Phenotype Frequency

The proportion of individuals in a population with a particular phenotype.

Genotype Frequency

The proportion of individuals in a population with a specific genotype.

Allele Frequency

The relative frequency of an allele at a genetic locus in a population.

Hardy-Weinberg Equilibrium

A principle stating that allele and genotype frequencies in a population will remain constant in the absence of evolutionary influences.

Genetic Drift

Change in allele frequencies due to random sampling effects, particularly in small populations.

Natural Selection

The process where organisms better adapted to their environment tend to survive and produce more offspring.

Mutation

A spontaneous change in DNA that can create new alleles.

Migration (Gene Flow)

The transfer of genetic variation from one population to another through the movement of individuals or gametes.

Founder Effect

Genetic drift that occurs when a small number of individuals establish a new population.

Bottleneck Effect

A sharp reduction in the size of a population due to environmental events, leading to a loss of genetic diversity.

Non-random Mating

Mating that occurs based on specific phenotypic or genotypic traits rather than random chance.

Positive Assortative Mating

Individuals select mates that are genetically more similar to themselves.

Negative Assortative Mating

Individuals select mates that are genetically less similar to themselves.

Demographic Stochasticity

Random variations in population growth rates due to differences among individuals in survival and reproduction rates.

Phenotypic Variation

The observable differences between individuals in a population, often influenced by genetic variation.

Allele Fixation

A situation where an allele reaches a frequency of 100% in a population, leading to the loss of alternative alleles.

Allele Loss

The complete absence of an allele in a population, often due to genetic drift.

Equilibrium Conditions

Specific conditions under which Hardy-Weinberg equilibrium can be achieved, such as no mutations, no selection, random mating, and no gene flow.