Transcript Food Chains and Food Webs

Food Chains
and
Food Webs
How energy moves in an ecosystem
OR
who eats who!?
Quick Review
We have already learned
several things about
ecosystems.
All things in can
ecosystem are either
abiotic or biotic.
Biotic factors are grouped
by what each organism
eats.
All of the energy in an
ecosystem starts with
the sun.
Producers use the sun to
get energy and make
their food through a
process called
photosynthesis.
Consumers have to eat
producers or other
consumers to get their
energy.
Decomposers get energy
from eating dead
consumers and
producers.
Organisms need this energy to live.
Energy moves through an
ecosystem when one organism
eats another organism.
This keeps the ecosystem going.
This energy pyramid is one way to show how energy
moves. Producers are always at the bottom of the energy
pyramid because they are the first things eaten. Notice
that the amount of energy is lost, or decreases, as more
organisms eat each other.
If we want to show the
ways energy moves
through an ecosystem
we use a food chain or
a food web.
Vocab Definition
Add this now to your vocab book
Food Chain: A food chain shows one path
of how energy moves through an
ecosystem (who-eats-who).
Food Web: A food web shows many paths
of how energy moves through an
ecosystem (who-eats-who). A food web is
made up of many different food chains.
Here is an example of a food chain.
Remember: Arrows are used to show
where the energy is going.
Here is an example of a food web.
Remember: Arrows are used to show
where the energy is going.
Turn to you partner and tell
them everything you learned
about food chains and food
webs and what they show us
about an ecosystem.
You could have mentioned that:
1. It shows use the way energy moves in an
ecosystem.
2. It shows us who-eats-who in an ecosystem.
3. It is made up of producers, consumers and
decomposers.
4. Arrows are used to show where the energy is
moving.
5. ……?
Now turn to your partner and
discuss the difference between
a food web and a food chain.
You could have said that:
1. A food chain shows one way energy
moves in an ecosystem but a food web
shows many ways energy moves.
2. A food web is made up of many different
food chains.
Draw your own food web with the following organisms. Don’t forget to include
arrows and remember that arrows show where the energy is moving.
Mouse
Fox
Owl
Snake
Berries
Rabbit
Squirrel
Leaves
Grasshopper
Frog
(collect vocab books!!)