What term describes each step in the transfer of energy and matter within a biological community?

• A. Trophic level
• B. Ecological niche
• C. Population
• D. Biome

Answer: (A)

The idea being tested is trophic levels: each step in the transfer of energy and matter in a biological community corresponds to a feeding level. Producers at the base capture energy from the sun, primary consumers eat those producers, secondary consumers eat the primary consumers, and so on. Energy decreases as you move up each level, which is why higher levels support fewer organisms. Ecological niche, population, and biome describe different concepts—niche is an organism’s role in its environment, population is a group of individuals of the same species in an area, and biome is a large regional community with characteristic climate and organisms. So the term for each step in the energy/matter transfer is trophic level.