Chapter 56 - Communities - 56.1 - Communities Are Groups of Interacting Species Occurring Together in Space and Time - 56.1 Recap - Learning Outcomes - Page 1210: 3

The amount of energy in a system drastically decreases as it goes up trophic levels. Approximately 90% of the energy in one trophic level makes it to the next level up, since much of it is lost during cellular respiration and in unconsumed material.

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