Food Chains & Food Webs

TERMINOLOGY

Producer – an organism that makes its own food.

Consumer – an organism that eats another organism for food.

WHAT DO THESE THINGS HAVE IN COMMON?

FOOD CHAINS A food chain is a sequence

linking organisms that feed on each other.

Ex. Grass grasshopper frog

snake

TROPHIC LEVELS

Each organism in a food chain occupies a different feeding level, or trophic level.

The 1st trophic level is ALWAYS a producer. It feeds itself by making its own food through photosynthesis.

TROPHIC LEVELS

The 1st consumer or primary consumer is the organism that eats the producer. It is a herbivore.

The 2nd consumer or secondary consumer eats the herbivore. It is the 1st carnivore.

TROPHIC LEVELS

The 3rd consumer or tertiary consumer eats the primary carnivore (secondary consumer).

This trend can continue for multiple trophic levels.

TROPHIC LEVELS

Which trophic level would you occupy if you ate:

o a bowl of cornflakes?o a salmon that just ate a

herbivorous fish?o a steak?

FOOD CHAINSIn our original food chain, each

organism has a specific role(s):- The grass is the producer (1st

trophic level)- The grasshopper is the primary

consumer (2nd trophic level)- The frog is the secondary

consumer AND the primary carnivore (3rd trophic level)

- The snake is the tertiary consumer AND the secondary carnivore (4th trophic level)

WHAT DO THESE THINGS HAVE IN COMMON?

FOOD WEBS

A food web is a series of interconnected food chains all drawn in one picture. It shows all possible food chains given a number of organisms.

FOOD WEBS

FOOD WEBS

FOOD WEBSCreate a food web using the

following animals:

Grass, deer, rabbit, hawk, snail, algae, fish, minnow, raccoon, crane, mouse, snake, fox, owl