In a simple food chain, how does energy flow between trophic levels?

• A. Energy flows from consumers to producers
• B. Energy flows from producers to consumers
• C. Energy flows only within decomposers
• D. Energy is created by producers

Answer: (B)

Energy in an ecosystem moves from the organisms that capture energy from sunlight to the organisms that eat them. Producers like plants and algae trap light and store chemical energy in their tissues. When a primary consumer eats a producer, that stored energy becomes part of the consumer, though much is used for metabolism and released as heat. This energy transfer continues up the chain as predators eat prey, but only a small portion moves to the next level each time because most energy is lost as heat or used for life processes. Because of this pattern, energy flows from producers to consumers, not the other way around, and energy isn’t created by producers—it’s captured from sunlight and transformed into biomass.