Energy Flow in Food Chains, Food Webs, & Energy

Pyramids

Mrs. Joelle R. KingScience Teacher

Food Chains• Food chains use pictures or words

and arrows to show the movement of energy through the trophic levels of organisms.• The trophic level of an organism

indicates the position that the organism occupies in the food chain.• It shows what it eats and what eats

it.

Producers & ConsumersThe levels are numbered according to how far

the particular organism is along the chain.

• Producers are at level 1. (Plants are producers because they produce their own food.)

• Herbivores are at level 2. (consumer)• Predators are at level 3. (consumer)

And so on…

Anything that cannot make its own food must eat to

survive.

It must “consume” its food!

It is a consumer.

The owl eats the snake

that ate the frog that ate

the caterpillar

that ate the flower.

Follow the food chain from producer to top level

consumer.

Note: There’s something

wrong.What is it?

FOX EATS RABBIT THAT ATE PLANT.

Why does this look more like a “cycle” than a chain?

Let’s discuss this one in detail.

Why is the SUN in this

picture?

In this food chain, what is the producer?

What is the first level consumer?

What is the second level consumer?

Is the polar bear the 3rd level consumer? Explain.

This picture shows the trophic levels.

TrophicLevels

Food Webs• Food webs describe the organisms

found in interconnecting food chains using pictures or words and arrows.

• In other words, food webs are a bunch of food chains all together!

• They describe the complex patterns of energy flow in an ecosystem by modeling who consumes whom or what.

Let’s follow a few food

chains found in this food

web.

There are a lot of arrows

here, but they’re easy to follow.

Try it.

Food Webs are EASY!

Energy Pyramids• An energy pyramid shows the

amount of energy that moves from one trophic level to another in a food chain.

• The most energy is available at the producer level of the pyramid.

• The availability of energy decreases as it moves up the energy pyramid.

The most energy is at the producer level – the base of the pyramid.

The Energy Pyramid

Who needs the most energy to survive?

EnergyPyramid

Awesome Web Site!http://science-class.net/Ecology/energy_transfer.htm

•Let’s take a look at the above web site relating to ecology and energy transfer.

Another Cool Sitehttp://www.harcourtschool.com/activity/food/food_menu.html

After we look at the above web site, we’ll go on to view the BrainPop video entitled FOOD CHAINS.

The BrainPop videos provide further enrichment of topics discussed in class and are interesting as well as easy to understand!

www.brainpop.com

Making a Model Let’s make a model of an energy pyramid.

The model you will construct will be simple. It will show pictures of the producers and consumers at each level, the names in words, and the trophic levels.

The good news is that this model really is perfect for meeting our objectives relating to energy pyramids.

Make sure you follow all instructions for proper completion of the model.

Acknowledgements• All pictures were obtained from various

sources on Google Images.• None of the pictures/illustrations are

mine.• Credit is given to all

artists/photographers for their work.