Which diagram is used to visualize the total energy present at each step in a food chain?

• A. Biomass pyramid
• B. Number pyramid
• C. Energy pyramid
• D. Food web

Answer: (C)

When energy moves through an ecosystem, most of it is lost as heat at each transfer, so the amount of usable energy declines as you move from producers up to top predators. The diagram that best shows how much energy remains at each step of a food chain is the energy pyramid. It’s typically drawn with the largest energy at the bottom and progressively smaller amounts higher up, reflecting the energy that is actually available to each successive trophic level. This contrasts with a biomass pyramid, which shows mass at each level, a number pyramid, which shows how many individuals there are at each level, and a food web, which maps who eats whom rather than how much energy is present.