Final answer:
The remaining 90% of energy after only 10% is transferred to the next trophic level is used for metabolism, generating heat that dissipates into the environment, and is lost through excretion as waste.
Step-by-step explanation:
If only 10% of the energy transfers to the next level in a food chain, the remaining 90% of the energy is primarily lost in multiple ways. A large portion of this 90% go towards metabolic processes within the organisms at the current trophic level, such as growth, repair, movement, and other life functions. These processes generate heat, which is then dissipated into the environment. Additionally, some energy is also lost as waste through excretion when organisms cannot completely digest the food they consume.
Energy that enters an ecosystem, such as light energy from the sun, is transformed into chemical energy through processes like photosynthesis in plants. However, as energy flows from one trophic level to the next, only about 10% is typically passed on, while the remaining 90% goe elsewhere, ultimately maintaining the efficiency of the ecosystem's energy transfer.