Food Chain, Food Web, and
Food Pyramid Lab
Name _________________________
Date ____________________
Period _________
Objective: A2 - Analyze the flow of mater & energy through trophic levels using various models, including
food chains, food webs, & ecological pyramids
* Focus Question:
Why should the number of prey be greater than the number of predators in a balanced ecosystem?
________________________________________________________________________________________
Background Information
A food chain shows how each living thing gets its food. Most food chains have no more than four or five links because the animals at
the end of the chain would not get enough food (and hence energy) to stay alive. Most animals are part of more than one food chain
and eat more than one kind of food in order to meet their food and energy requirements. These interconnected food chains form a food
web. Arrows are drawn from food source to food consumers; in other words, you can substitute the arrows with the words "eaten by".
An ecological food pyramid is a graphical representations of the trophic structure of ecosystems.
Materials
Bag with various organisms and arrows
Pyramid of numbers
Procedures and Questions
1. Examine the pictures on the cards. Sort them by producer, primary consumer, secondary consumer, and
tertiary consumer by making 5 food chains and fill in the chart below. The chart below will not be completely filled in.
Here’s an example of what the lab table should look like:
Producer pic
Primary consumer pic
Secondary consumer pic
Tertiary consumer pic
Producer pic
Primary consumer pic
Secondary consumer pic
Tertiary consumer pic
Producer pic
Primary consumer pic
Secondary consumer pic
Producer pic
Primary consumer pic
Secondary consumer pic
Producer pic
Primary consumer pic
Secondary consumer pic
Producers
Primary Consumers
Secondary Consumers
Tertiary Consumers
2. After recording your data in the table above, keep out the 2 food chains that start with the grain & the carrots.
Put all other picture cards back in the baggie. Keep the extra arrows out for #3. Record the 2 food chains below.
Make sure to draw arrows between the organisms with the flow of energy.
1-_____________________________________________________________________________________
2-_____________________________________________________________________________________
3. With the 2 food chains from #2, construct a food web by interconnecting them with arrows showing possible
feeding relationships and record in the box below. For example, the rabbit can eat the carrots & the grain; the
owl can eat the rabbit, the mouse, & the snake; etc. Note: You do not have to draw pictures, writing names is okay.
Food Web
Example
4. Explain why a food web is a more realistic representation of feeding relationships in an ecosystem than a
food chain.
__________________________________________________________________________________________
__________________________________________________________________________________________
5. Select one food chain from your food web above and arrange it on the pyramid of numbers on the lab table.
Record below.
6. Clean up the lab table by returning the rest of the cards and arrows to the bag.
Analysis
Use the picture to the right to answer the next 5 questions.
1. What trophic level represents the primary consumer? _____
2. What trophic level represents the producers of an ecosystem? _____
3. Where is the least amount of energy available in an ecosystem? _____
4. In which trophic level would you find the greatest concentration of pesticides? _____
5. What level of the pyramid would you consume to receive the most energy? ______
A
B
C
D
Use the picture below to answer the next 3 questions.
_____ 6. What do the arrows represent?
a. Eating patterns of the consumers
b. Feeding relationships of the organisms
c. Path of energy flow
d. Cycling of nutrients in the ecosystem
7. Circle the secondary consumers in the food web above.
_____ 8. Secondary consumers in the food web above include ___.
a. Squirrels, rabbits, frogs
b. Frogs, beavers, owl
c. Snakes, owl, fox
d. Bird, frog, mountain lion
_____ 9. Which organism to the right should have the largest biomass? →
a. bluetit
b. caterpillar
c. sparrowhawk
d. oak tree
_____ 10.This food chain can be found in the coastal waters of Virginia.
The population of which organisms in the food chain would be
the first to decline if commercial fishing over-harvested
shrimp? [VA08 EOC]
A Algae
B Zooplankton
C Damselfish
D Barracuda
Labeling a Food Web
1. For the food web, label each organism: (Some may have more than one label)
P = Producer, 1 = Primary Consumer, 2= Secondary Consumer, 3 = Tertiary Consumer
2. Now label each animal as either a:
H = herbivore, C = carnivore, O = omnivore