FOOD WEBS

FOOD CHAINS Food Chain- A sequence of organisms that eat one another in an ecosystem.

FOOD WEBS Food Web- A diagram that shows all the feeding relationships in an ecosystem.

WHO’S INVOLVED Food Webs have 3 groups of organisms that are involved. Producers Consumers Decomposers

PRODUCERS Producer- An organism that is able to make its own food through photosynthesis. Food webs always start out with the producers in an ecosystem.

CONSUMERS Consumer- An organism that eats other organisms Primary Consumer- Eats producers Secondary Consumers- Eat primary consumers Tertiary Consumers- Eat secondary consumers

PRIMARY CONSUMERS

SECONDARY COMSUMERS

TERTIARY COMSUMERS

CONSUMERS Primary, Secondary, and Tertiary consumers often have more than one type of feeding relationship that may make them hard to fit into just one group. Example: Trout Secondary Consumer Trout Mayfly Primary Consumer Producer Planktonic Algae

DECOMPOSERS Decomposer- An organism that consumes part of dead organisms and decaying matter.

Food webs like the one below can sometimes be confusing.

Tertiary Consumers Human Snake Eagle Secondary Consumers Salamander Frog Trout Decomposers Primary Consumers Dragonfly Mayfly Producers Phytoplankton

ENERGY ARROWS Arrows on a food web are always drawn FROM food source TO food consumer.

TYPES OF CONSUMERS Herbivore- Organism that eats ONLY PLANTS Will always be a primary consumer. Carnivore- Organism that eats ONLY MEAT Carnivores that eat Herbivores are secondary consumers Carnivores that eat other Carnivores are tertiary consumers Omnivore- Organisms that eat BOTH plants and meat.