APES UNITED 1

Ecosystem

A defined area where living things interact with nonliving parts of the environment as a system, through exchanges of energy and matter.

Biotic components

All living (or once-living) organisms including plants, animals, fungi, bacteria, and protists.

Abiotic components

Nonliving physical and chemical factors such as sunlight, temperature, water, soil, dissolved oxygen, salinity, pH, and nutrient availability.

Generalists

Organisms able to survive on a wide variety of food resources and withstand a wide range of environmental conditions.

Specialists

Organisms with a specific or limited number of prey and prone to extinction; sensitive to environmental change.

Symbiosis

Any close, long-term biological interaction between two different organisms.

Amensalism

A type of symbiotic interaction where one species is harmed and the other is unaffected.

Commensalism

A type of symbiotic interaction where one species benefits and the other is unaffected.

Mutualism

A type of symbiotic interaction where both species benefit.

Parasitism

A type of symbiotic interaction where one species benefits while the other is harmed.

Predation

An interaction where predators hunt and kill prey.

Law of Tolerance

The principle stating that the existence, abundance, and distribution of a species depend on its tolerance level to physical and chemical factors.

Limiting factor

Any environmental factor that restricts population growth, abundance, or distribution.

Carrying capacity

The maximum population size an environment can sustain over time given available resources and limiting factors.

Feedback loop

Refers to interactions within ecosystems that either stabilize or amplify change.

Habitat

The physical environment where an organism lives.

Niche

The role of an organism in its ecosystem, including how it gets energy and interacts with living and nonliving factors.

Biodiversity

The variety of life in an area, emphasizing its importance for ecosystem resilience, productivity, and ecosystem services.

Primary productivity

The rate at which producers convert solar energy into chemical energy stored as biomass.

Gross primary productivity (GPP)

Total energy captured by producers through photosynthesis.

Net primary productivity (NPP)

The energy remaining after producers meet their respiration needs; this is the energy available to consumers.

Bioaccumulation

The process by which a chemical builds up in an organism over time due to intake exceeding elimination.

Biomagnification

The process by which chemical concentration increases at higher trophic levels through the food chain.