Ap biology unit 8 mr falkin

Ecosystem

A biological community of interacting organisms and their physical environment, including both biotic and abiotic components, with nutrient cycling and energy flow.

Detritivore

A heterotroph that consumes decomposing organic material and contributes to the breakdown and recycling of nutrients (e.g., earthworms, some insects).

Ecological Niche

The sum of a species’ use of the biotic and abiotic resources in its environment; includes its role, habitat, interactions, and tolerance limits.

Parasitism

A symbiotic relationship in which one organism (the parasite) benefits at the expense of the host, which is harmed.

Predation

An interaction in which one species (the predator) kills and consumes another species (the prey), influencing population dynamics and natural selection.

Mutualism

A type of symbiotic relationship in which both organisms benefit from the interaction (e.g., pollinators and flowering plants).

Commensalism

A symbiotic relationship in which one organism benefits while the other is neither helped nor harmed.

Symbiosis

An ecological relationship between organisms of two different species that live in close contact, including mutualism, commensalism, and parasitism.

Coevolution

The reciprocal evolutionary change in interacting species, driven by natural selection (e.g., flowering plants and their pollinators).

Keystone Species

A species that has a critical role in maintaining the structure of an ecological community; its removal drastically alters the ecosystem.

Invasive Species

A non-native species introduced to an ecosystem that spreads rapidly and disrupts native communities by outcompeting native species or altering habitats.

Migration

The regular, often seasonal, movement of organisms from one habitat to another, usually for breeding or climate-related reasons.

Imprinting

A form of learning occurring at a specific life stage (critical period) in which an animal forms attachments or develops specific behaviors.

Behavior

An organism’s response to environmental stimuli, which can be innate (genetically programmed) or learned through experience.

Pheromones

Chemical signals secreted by animals that trigger a social response in members of the same species, often related to mating or territory.

Population

A group of individuals of the same species that live in the same area and interbreed, producing fertile offspring.

Immigration

The influx of new individuals into a population from other areas, increasing population size.

Emigrate

To leave a population or geographic area, potentially reducing the population size in the origin area.

Mortality

The rate of death in a population, often expressed as deaths per unit time or per 1,000 individuals.

Habituation

A non-associative learning process where an organism decreases or ceases its responses to a repetitive, harmless stimulus.

Biomass

The total mass of all living matter in a given area or ecosystem, often used to quantify energy availability at trophic levels.

Species Diversity

A measure of biodiversity that combines species richness (number of species) and species evenness (relative abundance).

Species Richness

The number of different species represented in a community, without considering population size or distribution.

Primary Producer

Autotrophic organisms (typically plants, algae, and some bacteria) that convert solar or chemical energy into organic compounds via photosynthesis or chemosynthesis.

Primary Consumer

An organism that feeds on primary producers; typically herbivores in the first trophic level above producers.