Which statement best describes the role of producers in an ecosystem's energy flow?

• A. They convert sunlight into chemical energy
• B. They consume other organisms
• C. They decompose waste
• D. They release energy as heat

Answer: (A)

The main idea is that producers start the energy flow in an ecosystem by turning sunlight into chemical energy. Through photosynthesis, producers like plants and algae capture light energy and convert it into sugars stored as chemical energy. This stored energy becomes the fuel that all other organisms rely on, since consumers obtain energy by eating producers or other organisms, and decomposers recycle nutrients. Energy is released as heat in metabolic processes at all levels, but that isn’t the primary job of producers. An example is a green plant using sunlight to make glucose, providing the energy base for the rest of the ecosystem.