Sample Data - Lab: Energy Transfer in the Ecosystem

Name______

Class Data Table Food Chain length Total Volume of Volume of water in % Efficiency of (in links) water taken from end containers energy transfer the large bucket 1 8740 5500 63 2 7360 2005 27 3 6900 1070 16 4 5980 330 6 5 5520 110 2 Calculation: Efficiency of energy transfer = Volume of water in end container (ml) x 100 Volume of water from bucket (ml) Graph: Your results should be graphed to show the relationship between the length of the food chain and energy transfer efficiency.

Analysis: 1. What does the water in the 5-gallon bucket represent? Explain. The sun; the sun is the main source of energy for all living things 2. What does the water you receive from another food chain member represent? Energy that the consumer receives 3. What does the spilled water represent? Explain. Energy “lost”; each time energy is transferred some is lost (unavailable to the consumer) 4. What does the water in the end container represent? Useable energy taken in by the highest level consumer 5. In a one-link food chain, what process is being modeled? Photosynthesis 6. Consider all of the “energy” that was lost from the food chain during the activity. In actual ecosystems, where does this energy go? (2 ways) It is given off as heat and some is wasted (uneaten parts and indigestible parts) 7. Is there a limit to the length of a food chain? Explain. Yes, generally food chains are limited to four levels – since some energy is “lost” after each transfer, there is not enough energy available to support an organism at the fifth or sixth link.