Which of the following best summarizes the flow of energy and cycling of chemicals in a terrestrial ecosystem?

• A. Energy and chemicals are both recycled indefinitely within the ecosystem.
• B. Both energy and chemicals flow in a one-way direction from producers to consumers and are lost as heat.
• C. Energy flows one-way from the sun to producers to consumers, while chemicals cycle between biotic and abiotic components.
• D. Chemicals flow one-way through the ecosystem, while energy is recycled between organisms.

Answer: (C)

Verified step by step guidance

1. Understand the distinction between energy flow and chemical cycling in an ecosystem. Energy flows in one direction, while chemicals are recycled within the ecosystem.
2. Energy originates from the sun and is captured by producers (plants, algae, etc.) through photosynthesis. Producers convert solar energy into chemical energy stored in glucose molecules.
3. Consumers (herbivores, carnivores, omnivores) obtain energy by consuming producers or other consumers. As energy is transferred through trophic levels, some is lost as heat due to metabolic processes.
4. Chemicals, such as carbon, nitrogen, and phosphorus, cycle between biotic (living organisms) and abiotic (soil, water, air) components of the ecosystem. These cycles are facilitated by processes like decomposition, respiration, and nutrient uptake.
5. Summarize: Energy flows one-way from the sun to producers to consumers and is eventually lost as heat, while chemicals are continuously recycled between biotic and abiotic components of the ecosystem.