Population Genetics and Evolution

These flashcards cover key vocabulary and concepts related to population genetics and evolution that are important for understanding genetic diversity, evolution processes, and their implications on organisms.

Nucleotide

The basic building block of DNA, consisting of a sugar, phosphate group, and a nitrogenous base (adenine, guanine, cytosine, or thymine).

Codon

A sequence of three nucleotides in DNA or RNA that encodes for a specific amino acid.

Mutation

A permanent alteration in the DNA sequence that makes up a gene.

Genotype

The genetic constitution of an individual, representing all the alleles inherited.

Phenotype

The observable physical traits or characteristics of an organism resulting from the genotype.

Allele

One of the different forms of a gene that may exist at a particular locus on a chromosome.

Homozygote

An individual that possesses two identical alleles for a particular gene.

Heterozygote

An individual that possesses two different alleles for a particular gene.

Dominant Allele

An allele that can mask the expression of a recessive allele in a heterozygous organism.

Recessive Allele

An allele that is masked by the presence of a dominant allele in a heterozygous organism.

Hardy-Weinberg Equilibrium

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

Fitness

The ability of an organism to survive and reproduce in its environment.

Natural Selection

The process by which certain traits become more common in a population due to their beneficial effects on fitness.

Genetic Drift

Random changes in allele frequencies in a population due to chance events.

Inbreeding

Mating between closely related individuals which can lead to an increase in the likelihood of offspring inheriting harmful genetic traits.

Outcrossing

Mating between unrelated individuals, which can introduce new genetic variation into a population.

Founder Event

A phenomenon that occurs when a small number of individuals colonize a new area, leading to reduced genetic variation in the new population.