Engage: Who Burned the Food?

Put your hand on top of your head and let it rest there a minute. What do you feel? Did you notice it was warm up there? Why is heat coming from the top of your head? Where is it generated? Did you say it's generated from cell metabolism? Good answer!

The term cell metabolism stands for all the chemical reactions the cell uses to process matter and access energy to function correctly. One way cells accomplish this is by breaking down the foods we eat for the raw materials and the energy that was stored in the chemical bonds. In this resource, you'll look at matter and energy in food from a consumer's perspective. After all, we're consuming food to nourish our cells but as consumers, we also play a part in a bigger picture known as the ecosystem.

Watch the the video below and get ready to take down some data so you can answer two questions about the available matter and energy in yummy cashews.

Now that you have seen the video, collected data, and made observations, it's time to answer a few questions. Don't worry! The quiz doesn't count but you can use it to check for understanding.

Explore: The Food Chain

Pre-match/Post-match Activity

First, match the label and definition to the appropriate organism in the food chain represented in the animation. Next, click "The Food Chain Gang" to read about food chains, food webs, and the interdependence of organisms. Last, take a second opportunity to match the cards. Did you do a better job remembering the vocabulary and which role each organism has in the food chain?

You can also access a copy of the "The Food Chain Gang" in "Related Items" at the bottom of the page.


What is happening to the energy as it flows up the food chain in the graphic above? Some is lost as heat, but what do the organisms at each trophic level use? To find out, copy the data table on your own paper and then list each organism's name and role into the appropriate box. Follow the example below to calculate the percent of energy transferred between trophic levels 1 to 2, 2 to 3, and 3 to 4. Leave the box in the upper-right corner empty.

Level 2     95.0Level 1    900.0x100=% energy transferred

Explain: Energy Flows and Matter Cycles

Watch the movie below. In fact, you can sing along if you want. Once you have finished, check your understanding of the vocabulary and concepts you have learned so far in your study of energy and matter in ecosystems.

Video downloaded from YouTube 4/14/2011.

Elaborate: Putting It All Together

It's your turn to put it all together. Drag the card that comes out of the pipe to the appropriate trophic level in the food pyramid. When all the cards are in the correct position, lines will appear connecting food chains in the food web. Use the organism descriptor cards in the "East Texas Food Web" document and download and print "The East Texas Food Pyramid" to help determine the proper trophic level placement of the organism.

*Note: Some organisms in the animation activity are represented by two cards because they belong to more than one food chain.