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Free Energy and Ecological Relationships

APBIO-IZJWEB

The ecological pyramid illustrated below shows the transfer of energy through trophic levels:

"Ecological Pyramid." Wikipedia. Wikimedia Foundation, 01 June 2015. Web. 18 Apr. 2016.

Which of the following statements BEST describes differences in free energy availability between organisms at different trophic levels?

A

There is no trophic level after apex predators because there is no more free energy available to sustain anything.

B

Primary producers use the most free energy, which limits what is available to all the remaining trophic levels.

C

Free energy is conserved in food chains and webs, as the first law of thermodynamics mandates.

D

Free energy is recycled in ecological pyramids via decomposers.