Bio Vocab Flashcards
Natural Selection
The process by which organisms with favorable traits survive and reproduce more successfully than others.
Adaptation
A heritable trait that increases an organism’s chance of survival and reproduction in a particular environment.
Fitness
The ability of an organism to survive and reproduce in its environment.
Genetic Variation
Differences in DNA sequences among individuals in a population.
Selective Pressure
Any environmental factor that influences which individuals survive and reproduce.
Mutation
A change in a DNA sequence that can introduce new traits into a population.
Genetic Drift
A random change in allele frequencies in a population, especially in small populations.
Bottleneck Effect
A sharp reduction in the size of a population due to environmental events, resulting in reduced genetic diversity.
Founder Effect
A reduction in genetic variation when a small group of individuals establishes a new population.
Gene Flow
The movement of alleles between populations due to migration.
Hardy-Weinberg Equilibrium
A principle stating that allele frequencies in a population remain constant if certain conditions are met (no evolution).
Directional Selection
A type of natural selection that favors one extreme phenotype over the others.
Stabilizing selection
A type of natural selection that favors the intermediate variants by acting against extreme phenotypes.
Disruptive Selection
A type of natural selection that favors individuals at both extremes of a trait, reducing the intermediate form.
Sexual Selection
A form of natural selection in which individuals with certain traits are more likely to obtain mates.
Artificial Selection
The intentional breeding of organisms by humans for specific traits.
Speciation
The formation of new and distinct species through the process of evolution.
Allopatric Speciation
Speciation that occurs when populations are geographically separated.
Sympatric speciation
Speciation that occurs without physical separation of members of the population.
Reproductive Isolation
When biological barriers prevent species from interbreeding and producing fertile offspring.
Prezygotic Barrier
Reproductive barriers that occur before fertilization, such as behavioral or mechanical isolation.
Postzygotic barriers
Reproductive barriers that occur after fertilization, preventing the offspring from surviving or reproducing.
Adaptive Radiation
The diversification of a group of organisms into forms filling different ecological niches.
Convergent Evolution
The process where unrelated species evolve similar traits due to similar environmental pressures.
Divergent Evolution
The accumulation of differences between closely related populations leading to speciation.
Homologous Structures
Structures that are similar due to shared ancestry but may have different functions.
Analogous Structures
Structures that serve similar functions but evolved independently in different species.
Vestigial Structures
Structures that have lost their original function through evolution.
Molecular Evidence
Evidence for evolution found in similarities in DNA and protein sequences among species.
Phylogenetic Tree
A diagram showing evolutionary relationships among various species based on genetic or physical traits.
Cladogram
A type of diagram that shows relationships based on shared derived characteristics.
Co-evolution
The reciprocal evolutionary change in two or more species interacting closely with one another.
Extinction
The permanent loss of all members of a species.
Endosymbiotic Theory
The theory that eukaryotic cells evolved from prokaryotic cells that formed symbiotic relationships.
Punctuated Equilibrium
The theory that species evolve in rapid bursts of change followed by long periods of stability.
Habitat Isolation
Two species occupy different habitats within the same geographic area, reducing the likelihood of encountering each other for mating.
Temporal Isolation
Species breed during different times of the day, seasons, or years, preventing them from mating.
Behavioral Isolation
Species have distinct courtship rituals or mating behaviors that prevent them from recognizing each other as potential mates.`
Mechanical Isolation
Morphological differences between species, such as incompatible genitalia, prevent successful mating.
Gametic Isolation
Sperm of one species cannot fertilize the eggs of another species, even if they come into contact.
