Which term refers to the series of steps in which organisms transfer energy by eating and being eaten?

• A. Food chain
• B. Food web
• C. Energy pyramid
• D. Nutrient cycle

Answer: (A)

Energy moves through ecosystems through feeding relationships, and a food chain is a simple, linear way to represent that flow. It starts with a producer that captures energy from the sun, followed by primary consumers that eat the producers, then secondary consumers that eat those herbivores, and so on. As energy moves from one level to the next, most of it is lost as heat from metabolic processes, so only a portion is transferred upward. This creates a step-by-step sequence of who eats whom and how energy is passed along.

A food web would show many interconnected feeding relationships, not just a single path. An energy pyramid highlights how much energy is available at each trophic level rather than the actual sequence of who eats whom. A nutrient cycle deals with the movement of elements like carbon or nitrogen, not energy transfer.