AP Environmental Science Unit 2 Biodiversity Vocabulary

Surface Tension

The cohesive force between liquid molecules at the surface creates a film-like quality, allowing certain objects to float or move on water without sinking.

Capillary Action

The ability of a liquid to flow in narrow spaces against gravity due to the adhesive forces between the liquid and surrounding materials, often observed in plants as water moves from roots to leaves.

pH (Acid/Base)

A measure of the acidity or alkalinity of a solution, ranging from 0 to 14, with lower values indicating acidity, higher values indicating basic, and 7 being neutral.

Marine Mammal Act

A legislation aimed at the protection and conservation of marine mammals, establishing guidelines and regulations for their management, habitat preservation, and research.

Endangered Species

Species at risk of extinction due to habitat loss, overexploitation, and other threats, often protected by laws and conservation efforts.

Threaten Species

Species that face dangers leading to potential extinction, often due to environmental changes and human activities.

Convection of Biological Diversity

An international agreement aimed at conserving biological diversity, promoting sustainable use of its components, and ensuring fair sharing of benefits arising from genetic resources.

Edge Habitat

A habitat that occurs at the boundary between two or more ecosystems, often characterized by unique environmental conditions and species diversity.

Biosphere Reserve

A protected area designated to conserve biodiversity, promote research, and support sustainable development, usually comprising core, buffer, and transition zones.

Species Richness

The number of different species present in a given area or ecosystem, indicating its biodiversity.

Species Evenness

A measure of how evenly the individuals of different species are distributed within a community, indicating the abundance relative to each species.

Phylogeny

The evolutionary history and relationships among species, often represented as a phylogenetic tree, which shows how species have diverged from common ancestors.

Shannon’s Index of Biodiversity

A mathematical formula used to quantify biodiversity in a community by accounting for both species richness and evenness, providing a single value that reflects the diversity of life present.

Evolution

The process by which different kinds of living organisms developed from earlier forms during the history of the Earth, driven by natural selection and genetic variation.

Microevolution

The small-scale evolutionary changes that occur within a population, typically involving changes in allele frequencies over time, often in response to environmental pressures.

Macroevolution

The major evolutionary changes that occur over long periods of time, leading to the emergence of new species and higher taxonomic groups, often involving significant morphological changes.

Genes

The basic units of heredity in living organisms, made up of DNA, that determine specific traits by encoding for proteins.

Genotype

The genetic constitution of an individual, determining specific traits by the combination of alleles inherited from both parents.

Phenotype

The observable physical and physiological traits of an organism, which are influenced by its genotype and environmental factors.

Mutation

A change in the DNA sequence of an organism's genome, which can result in new traits or variations and can be beneficial, neutral, or harmful.

Recombination

The process by which genetic material is rearranged during sexual reproduction, leading to the creation of new allele combinations in offspring.

Evolution by Artificial Selection

The process where humans selectively breed organisms for desired traits, influencing the genetic makeup and evolution of species.

Evolution by Natural Selection

The process by which organisms better adapted to their environment tend to survive and produce more offspring. This mechanism drives changes in population traits over generations.

Fitness

The ability of an organism to survive and reproduce in its environment, contributing to the gene pool of the next generation.

Adaptations

Are physical or behavioral traits that enhance an organism's ability to survive and reproduce in a specific environment.

Gene Flow

The transfer of genetic variation from one population to another, which can increase genetic diversity and influence evolutionary processes.

Genetic Drift

The process by which allele frequencies in a population change over generations due to random sampling of organisms, which can lead to the loss or fixation of alleles.

Bottleneck Effect

A significant reduction in population size due to environmental events or human activities, leading to a loss of genetic variation. This effect can drastically change the allele frequencies in the surviving population.

Founder Effect

The loss of genetic variation that occurs when a small group of individuals becomes isolated from a larger population, leading to a new population that may have different allele frequencies.

Geographic Isolation

The separation of populations due to physical barriers such as mountains, rivers, or distances, leading to restricted gene flow and the potential for speciation.

Reproductive Isolation

A condition in which different species are prevented from interbreeding due to various barriers, leading to the development of distinct species.

Allopatric Speciation

The process of speciation that occurs when populations are geographically isolated, preventing gene flow and leading to evolutionary divergence.

Sympatric Speciation

The process of speciation that occurs within a shared habitat, often due to reproductive barriers despite geographic proximity, leading to the emergence of new species.

Genetically Modified Organisms (GMO)

Organisms whose genetic material has been altered using genetic engineering techniques, often to enhance desired traits such as resistance to pests or improved nutritional value.

Range of Tolerance

The range of physical and chemical conditions under which a species can survive and reproduce, including factors like temperature, moisture, and nutrient availability.

Fundamental Niche

The total range of environmental conditions where a species can exist and fulfill its role in the ecosystem without interactions or competition with other species.

Realized Niche

The actual conditions and resources in which a species exists and interacts with other species, shaped by competition and environmental factors.

Distribution

The way in which a species is spread out across a given area, including patterns of population density and habitat preferences.

Niche Generalist

A species that can thrive in a wide range of environmental conditions and utilizes a variety of resources, allowing it to adapt to different habitats.

Niche Specialist

A species that has a narrow ecological niche and is adapted to specific environmental conditions and resources, often making it more vulnerable to changes in its habitat.

Mass Extinction

An event in which a significant percentage of all life on Earth is wiped out in a relatively short period, often due to catastrophic events or significant environmental changes.

Population

A group of individuals of the same species that live in a specific area and interbreed, sharing genetic and demographic characteristics.

Community

A group of interacting populations of different species that inhabit the same area, sharing resources and influencing each other's abundance and distribution.

Population Ecology

The study of how populations interact with their environment, focusing on factors affecting population size, distribution, and dynamics.

Population Size (N)

The total number of individuals in a population at a given time, influencing its growth and stability.

Population Density

The number of individuals of a species per unit area or volume, providing insights into the spatial distribution and abundance of a population.

Population Distribution

The arrangement of individuals within a given space, which can be influenced by environmental factors and resource availability.

Sex Ratio

The ratio of males to females in a population, which can affect reproductive dynamics and population growth.

Age Structure

The composition of a population, categorized by the age of individuals, which influences growth rates and social dynamics.

Limiting Resource

A resource that is in short supply and restricts the growth, reproduction, or survival of a population in an ecosystem.

Density-dependent Factor

A biotic factor that affects population growth based on its density, such as competition, predation, and disease.

Carry Capacity (K)

The maximum population size that an environment can sustain indefinitely without degrading the habitat.

Density-independent Factor 

A factor that affects population size regardless of its density, including weather events and natural disasters.

California Condors (Endangered)

California condors are large birds native to North America, known for their impressive wingspan and scavenging behavior. Once near extinction, conservation efforts have helped increase their population, though they remain endangered due to habitat loss and lead poisoning.

Whooping Crane (Endangered)

The whooping crane is one of the tallest birds in North America, with a distinctive white plumage and a loud trumpeting call. Once on the brink of extinction, conservation programs have helped increase their numbers, but they still face threats from habitat destruction and climate change.