Which term describes energy transfer along a single food chain?

• A. Producer
• B. Decomposer
• C. Ecosystem
• D. Food chain

Answer: (D)

Energy flow in ecosystems is often described as a linear sequence of who eats whom. This exact pattern, where energy moves from one organism to another along a single path, is called a food chain. At the base are producers that capture energy from the sun, followed by primary consumers that eat producers, and higher-level consumers that eat those organisms. With each step, energy decreases because organisms use energy for metabolism and heat. The other terms are not descriptions of this linear transfer: a producer is the organism that begins the energy flow by photosynthesis; a decomposer breaks down dead material and recycles nutrients; an ecosystem is the larger system that includes all living and nonliving components and the energy transfers among them. A food web would show many interconnected food chains within the ecosystem. Therefore, the term describing energy transfer along a single food chain is food chain.