Lab 12 Model Ecosystems Lab Activity

Use your textbook, notes and this website to answer the pre lab questions. http://www.vtaide.com/png/foodchains.htm http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/F/FoodChains.html http://www.mbgnet.net/

 Pre Lab Questions:

1.  What is the ultimate source of energy for all organisms on this planet?

2.  List the biomes of the Earth.

3.  What biome do we live in here in Philadelphia?

4.  What attributes define a biome?

Click on the link below to access the online lab. http://www.mhhe.com/biosci/genbio/virtual_labs_2K8/pages/ModelEcosystems.html

Download and print the instructions for reference as you work through the lab.  As you work through the lab fill in the table below.  Use this information to answer the questions that follow contained in this document.

5. Complete all five ecosystems and record your data in Table 1.  The different ecosystems are listed across the top.  Fill in the data for each trophic level for each ecosystem.  For the numbers click on the [Pyramid of Numbers] button.  Next click on the [Pyramid of Energy] button. Calculate the Energy Conversion Efficiency Ratio (ECE) by dividing the higher trophic level energy by the energy one trophic level down.

List the organisms by name.  Provide the number of organisms present.  Provide the amount of energy present.  Calculate the ECE value.  This value will be a decimal value.  There is no ECE calculation for producers as you would have to divide the producer energy by the amount of energy provided by the sun.  We don’t have that value.  I have done the first column for you. :)

If you have any organisms out of place in the pyramid you will not be able to get the numbers you need to complete the calculations.  You need to move the various organisms to their correct positions in order to continue.

See the Table 1 in attachment

Just so you know exactly how to calculate the ECE

A = 623/6011 = .103

B = 61/623 = .097

C = 6/61 = .098

Post Lab Questions

6.  What is the relationship of numbers to energy as you go up the trophic levels?

7.  From the ecosystems you studied in this lab, which one is the most efficient?  Explain how you determined your answer.

8.  What would happen to an ecosystem without decomposers?

9.  From the ecosystems you studied in this lab, which one is the most productive?  (This cannot be the same as question 7)  Explain how you determined your answer.

Attachment:- bio table.docx