2.3 - Energy Flow in Ecosystems

autotroph

An organism that is able to make its own food, usually by photosynthesis

heterotroph

An organism that must each other living organisms for food

primary consumer

A consumer that eats only producers

secondary consumer

A consumer that eats primary consumers and possibly producers

tertiary (third-level) consumer

A consumer that eats secondary consumers and possibly eats secondary/primary consumers and producers

food chain

A simplified model that shows a single path for energy flow through an ecosystem

food web

A model that shows many interconnected food chains and pathways in which energy and matter flow through an ecosystem

herbivore

Heterotroph that consumes only plants

omnivore

Heterotroph that consumes both plants and animals.

carnivore

Heterotroph that consumes only animals.

trophic level

Each step in a food chain or food web

energy pyramid

Pyramid where each level represents the amount of energy that is available to that trophic level

pyramid of numbers

Pyramid where each level represents the number of individual organisms consumed by the level above it

pyramid of biomass

Pyramid where each level represents the amount of biomass consumed by the level above it

quaternary consumer

a consumer that eats tertiary consumers and possibly secondary or primary consumers

detrivore

organism that feeds on plant and animal remains and other dead matter