New York State 8th Grade Science - Ecology Key Terms

Ecosystem

A community of living (biotic) and non-living (abiotic) things interacting in an environment.

Biotic Factors

The living parts of an ecosystem (e.g., plants, animals, bacteria).

Abiotic Factors

The non-living parts of an ecosystem (e.g., water, air, temperature, sunlight).

Habitat

The specific place where an organism lives.

Niche

The role an organism plays in its environment, including what it eats and how it interacts.

Producer (Autotroph)

An organism (like plants) that makes its own food using sunlight (photosynthesis).

Consumer (Heterotroph)

An organism that eats other organisms for energy.

Herbivore

An organism that eats only plants.

Carnivore

An organism that eats only animals.

Omnivore

An organism that eats both plants and animals.

Decomposer

Organisms (like bacteria & fungi) that break down dead organisms and recycle nutrients.

Food Chain

A sequence that shows how energy moves from one organism to another.

Food Web

A network of interconnected food chains in an ecosystem.

Trophic Levels

The levels in a food chain (producers, primary consumers, secondary consumers, etc.).

Energy Pyramid

A diagram showing energy loss as it moves up trophic levels (only about 10% of energy transfers).

Photosynthesis

The process in which plants use sunlight, water, and carbon dioxide to make food (glucose) and oxygen.

Population

A group of the same species living in the same area.

Community

All the different populations that live together in an area.

Carrying Capacity

The maximum number of organisms an ecosystem can support.

Limiting Factor

Something that restricts population growth (e.g., food, water, space).

Predator

An animal that hunts and eats other animals.

Prey

The animal that is eaten by a predator.

Competition

When organisms fight for the same resources (food, water, shelter).

Symbiosis

A close relationship between two species.

Mutualism

A type of symbiosis where both species benefit (+/+).

Commensalism

A type of symbiosis where one species benefits and the other is unaffected (+/0).

Parasitism

A type of symbiosis where one species benefits and the other is harmed (+/-).

Biodiversity

The variety of life in an area; greater biodiversity makes ecosystems more stable.

Invasive Species

Non-native species that cause harm to an ecosystem.

Deforestation

The removal of forests, which leads to habitat loss and climate changes.

Pollution

Harmful substances introduced into the environment (air, water, soil pollution).

Global Warming/Climate Change

The increase in Earth's temperature due to greenhouse gases (like CO₂).

Renewable Resources

Resources that can be replenished naturally (e.g., solar, wind, water).

Nonrenewable Resources

Resources that cannot be easily replaced (e.g., fossil fuels).