Final answer:
Only about 10 percent of the energy at one trophic level is passed on to the next higher trophic level, while the rest is used for metabolic processes or lost to the environment as heat.
Step-by-step explanation:
The energy in the base of the food pyramid does not move fully to the levels above it due to energy loss at each trophic level. Only about 10 percent of the energy at one trophic level is passed on to the next higher trophic level, while the rest is used for metabolic processes or lost to the environment as heat. This loss of energy explains why there are rarely more than four trophic levels in a food chain or web.
In a food chain, only about 10% of energy moves to the next trophic level while the rest is lost mainly due to metabolic processes and as heat, following the second law of thermodynamics.
Why Only Some Energy Transfers Between Trophic Levels
Only about 10 percent of the energy at one trophic level is actually passed on to the next higher trophic level in a food chain or web. The remaining 90 percent of the energy is used by organisms for metabolism, growth, and repair, which generates thermal energy lost to the environment. Because of this significant energy loss, food chains rarely have more than four trophic levels as there's not enough energy left to support additional ones. The second law of thermodynamics explains the loss of energy as heat during these energy transfers, limiting the length of food chains.