BIO 319 Genetics - Variation in a Population and Hardy-Weinberg Equilibrium

Flashcards for key vocabulary related to population genetics, Hardy-Weinberg equilibrium, and sources of genetic variation.

Population Genetics

Examines genetic variation within a population and how it changes from one generation to the next.

Microevolutionary Processes

Population genetics explains microevolutionary processes, such as the shift in peppered moth populations in the UK during the 1800s.

Population

A group of individuals of the same species that occupy the same region and can interbreed.

Gene Pool

Consists of all alleles in a population.

Polymorphism

Describes genes that have two or more alleles, each with >1% frequency in a population.

Single-Nucleotide Polymorphism (SNP)

A single nucleotide difference in DNA sequence; 90% of human variants. Also called SNV (single-nucleotide variant).

Structural Variations

Genetic variations including deletions, insertions, and rearrangements.

Allele Frequency

Copies of allele / Total copies of gene in population.

Genotype Frequency

Individuals with genotype / Total number of individuals.

Hardy-Weinberg Equation

Relates allele and genotype frequencies: p^2 + 2pq + q^2 = 1

Hardy-Weinberg Equilibrium

Occurs when allele and genotype frequencies remain constant from generation to generation.

Deleterious Mutation

A mutation that decreases fitness relative to a wild-type organism.

Beneficial Mutation

A mutation that increases fitness.

Neutral Mutation

A mutation that has no effect on fitness.

Gene Duplication

Gaining an extra copy of a gene through various DNA recombination events. Duplicated genes evolve separately and diverge in function

Exon Shuffling

DNA recombination events that move an intact exon from one gene to another.

Horizontal Gene Transfer

Passing genetic material from one organism to another without a parent-offspring relationship.

Natural Selection

The process where beneficial traits become more common and detrimental traits become less common in a population due to differential survival and reproduction.

Fitness

A measure of reproductive success; individuals with higher fitness pass on more of their genes to the next generation.

Adaptation

A heritable trait that enhances the survival and reproductive success of an organism in a particular environment.

Directional Selection

Selection that favors one extreme phenotype, causing a shift in the population's genetic variance toward that extreme.

Stabilizing Selection

Selection that favors intermediate phenotypes, reducing genetic variance by selecting against extreme variations.

Disruptive Selection

Selection that favors two or more extreme phenotypes, increasing genetic variance by selecting against the intermediate phenotype.

Genetic Drift

Random changes in allele frequencies due to chance events; significant impact on small populations.

Bottleneck Effect

A sharp reduction in the size of a population due to environmental events or human activities, which reduces genetic diversity.

Founder Effect

The loss of genetic variation when a new colony is established by a small number of individuals

Hardy-Weinberg Equilibrium

Occurs when allele and genotype frequencies remain constant from generation to generation.

Deleterious Mutation

A mutation that decreases fitness relative to a wild-type organism.

Beneficial Mutation

A mutation that increases fitness.

Neutral Mutation

A mutation that has no effect on fitness.

Gene Duplication

Gaining an extra copy of a gene through various DNA recombination events. Duplicated genes evolve separately and diverge in function

Exon Shuffling

DNA recombination events that move an intact exon from one gene to another.

Horizontal Gene Transfer

Passing genetic material from one organism to another without a parent-offspring relationship.

Population Genetics

Examines genetic variation within a population and how it changes from one generation to the next.

Microevolutionary Processes

Population genetics explains microevolutionary processes, such as the shift in peppered moth populations in the UK during the 1800s.

Population

A group of individuals of the same species that occupy the same region and can interbreed.

Gene Pool

Consists of all alleles in a population.

Polymorphism

Describes genes that have two or more alleles, each with >1% frequency in a population.

Single-Nucleotide Polymorphism (SNP)

A single nucleotide difference in DNA sequence; 90% of human variants. Also called SNV (single-nucleotide variant).

Structural Variations

Genetic variations including deletions, insertions, and rearrangements.

Allele Frequency

Copies of allele / Total copies of gene in population.

Genotype Frequency

Individuals with genotype / Total number of individuals.

Hardy-Weinberg Equation

Relates allele and genotype frequencies: p^2 + 2pq + q^2 = 1

Hardy-Weinberg Equilibrium

Occurs when allele and genotype frequencies remain constant from generation to generation.

Deleterious Mutation

A mutation that decreases fitness relative to a wild-type organism.

Beneficial Mutation

A mutation that increases fitness.

Neutral Mutation

A mutation that has no effect on fitness.

Gene Duplication

Gaining an extra copy of a gene through various DNA recombination events. Duplicated genes evolve separately and diverge in function

Exon Shuffling

DNA recombination events that move an intact exon from one gene to another.

Horizontal Gene Transfer

Passing genetic material from one organism to another without a parent-offspring relationship.

Natural Selection

The process where beneficial traits become more common and detrimental traits become less common in a population due to differential survival and reproduction.

Fitness

A measure of reproductive success; individuals with higher fitness pass on more of their genes to the next generation.

Adaptation

A heritable trait that enhances the survival and reproductive success of an organism in a particular environment.

Directional Selection

Selection that favors one extreme phenotype, causing a shift in the population's genetic variance toward that extreme.

Stabilizing Selection

Selection that favors intermediate phenotypes, reducing genetic variance by selecting against extreme variations.

Disruptive Selection

Selection that favors two or more extreme phenotypes, increasing genetic variance by selecting against the intermediate phenotype.

Genetic Drift

Random changes in allele frequencies due to chance events; significant impact on small populations.

Bottleneck Effect

A sharp reduction in the size of a population due to environmental events or human activities, which reduces genetic diversity.

Founder Effect

The loss of genetic variation when a new colony is established by a small number of individuals

Hardy-Weinberg Equilibrium

Occurs when allele and genotype frequencies remain constant from generation to generation.

Deleterious Mutation

A mutation that decreases fitness relative to a wild-type organism.

Beneficial Mutation

A mutation that increases fitness.

Neutral Mutation

A mutation that has no effect on fitness.

Gene Duplication

Gaining an extra copy of a gene through various DNA recombination events. Duplicated genes evolve separately and diverge in function

Exon Shuffling

DNA recombination events that move an intact exon from one gene to another.

Horizontal Gene Transfer

Passing genetic material from one organism to another without a parent-offspring relationship.