Modeling Energy in Ecosystems Virtual Lab
Record evidence you completed for each task. Be sure to have titles and headings so the
information will make sense later when you read it.
Go to the site: http://www.mhhe.com/biosci/genbio/virtual_labs/BL_02/BL_02.html
1. Explore the simulation and read the writing on the left about energy flow through an
ecosystem.
2. There are five types of ecosystems modeled, try to place the organisms into the
correct “trophic level” on each model. Example: drag all the producers (plants) to
the part on the pyramid which reads producers, If you’re not sure which organisms
are herbivores, you can look them up on the computer (field guide) or use the
“check” feature.
3. Pick a favored ecosystem, just one. Complete the placement of all the organisms.
a. Sketch the simulation once it’s complete.
b. Record the data for “Pyramid of Numbers” and “Pyramid of Energy.”
c. Explain what you understand these numbers to mean.
4. Explain the following terms and give many examples. Producers, First Order
Heterotroph, Second Order Heterotroph, Third Order Heterotrophs, Decomposers.
5. Answer the following questions. Write with complete ideas. Sketch drawings and
show math calculations as needed.
a. Suggest reasons why the information represented in the pyramid of numbers
of animals of one of the ecosystems you studied may not truly represent that
ecosystem.
b. According to your data, what is the ratio of third-order consumers to
producers? Explain your answer.
c. Compare and contrast two of the ecosystems you studied. How is the energy
conversion efficiency similar or different? What is the energy difference
(percentage) between each trophic level?
d. Does the population size increase or decrease at higher trophic levels in the
pyramid of numbers of an ecosystem consisting of a tree, insects (that are
herbivores) and birds feeding on the insects? Explain your answer.
e. What might happen to an ecological pyramid of numbers in a forest
ecosystem if most of the deer were killed due to hunting by people and
disease?
f. What would happen to an ecosystem if the decomposers disappeared?
g. Could there be a food chain without herbivores and carnivores?