food chains & food webs unit 5: populations & ecosystems
TRANSCRIPT
What is a Food Chain?
A food chain is the path by which energy passes from one living thing to another.
(producers) use energy from sun, carbon dioxide, and water to make food
store energy in leaves, stems and roots
all other living things on earth get energy from plants.
consumers any form of life on earth that must eat other things to survivecannot make their own food
labeled by the number of steps they are away from plants, in the food chain
primary consumer eat plants to survive
get energy directly from plants
Ex: caterpillar eats a leaf; elephant eats bark of a tree; cow eats grass; squirrel eats nuts
secondary consumer organisms that eat primary consumers (plant eaters) to survive
get their energy from plants second-hand
Ex: owl eats mouse that eats berry; spider eats insect that eats leaf
tertiary consumer organisms that eat secondary consumers to survive
get their energy from plants third-hand
EX: hawk eats the fish, that ate the smaller fish, that ate the seaweed
top consumer not eaten by any other consumer on top of the food chain
can be primary, secondary or tertiary consumer
decomposers break down remains of dead organisms
help release trapped energy in dead organism back to the earth.
Types of Food Chains Aquatic- Water-related food chains with sea plants and animals
Terrestrial- Land-related food chains with land plants and animals
What is a Food Web?A more realistic way of looking at the relationship of plants and animals in an environment Several food chains linked together