Genetics and Hardy-Weinberg Principles

These flashcards cover key vocabulary related to genetic principles and the Hardy-Weinberg theory discussed in the lecture.

Heterozygous

An organism that has two different alleles for a trait (e.g., big E little e).

Homozygous recessive

An organism that has two identical recessive alleles for a trait (e.g., little e little e).

Genotype

The genetic makeup or allele combination of an organism.

Phenotype

The observable physical or biochemical characteristics of an organism, as determined by genetics.

Punnett square

A diagram that is used to predict the outcome of a particular cross or breeding experiment.

Allele frequency

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

Hardy-Weinberg equilibrium

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

Genetic drift

A mechanism of evolution that involves random changes in allele frequencies within a population.

Natural selection

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

Directional selection

A mode of natural selection in which an extreme phenotype is favored over other phenotypes, causing the allele frequency to shift over time in the direction of that phenotype.

Disruptive selection

A mode of natural selection that favors extreme over intermediate phenotypes.

Stabilizing selection

A mode of natural selection that favors intermediate variants and acts against extreme phenotypes.

Sexual dimorphism

Differences in male and female phenotypes that may be related to mating success.

Non-random mating

A pattern of mating that is not random, often influenced by traits that affect mate choice.