Which principle states that energy cannot be created nor destroyed?

• A. Energy
• B. Sediment
• C. Biomass
• D. Conservation of energy

Answer: (D)

Conservation of energy states that energy cannot be created or destroyed, only transformed from one form to another. In ecosystems, energy from the sun is captured by plants and stored as chemical energy in biomass. When organisms use that energy, it’s converted into other forms—like kinetic energy for movement or heat for maintaining body temperature—yet the total energy remains constant. This is why, even with losses as heat due to inefficiencies, the overall energy in a closed system is conserved. The other terms don’t express a rule about how energy behaves: energy describes a quantity, sediment is material in soil, and biomass is the amount of living matter. So the conservation of energy best fits the principle described.