In an ecosystem, the organism which changes light energy into stored chemical energy is the

Step 1: Analyze the question The question asks which organism converts light energy into stored chemical energy. That process is photosynthesis, so we need the group of organisms that carries it out.

Step 2: Explain the concept Photosynthesis is the process in which organisms containing chlorophyll (green plants, algae, and some bacteria) use light energy to turn carbon dioxide and water into glucose (food) and oxygen:

6CO₂ + 6H₂O → (light, chlorophyll) → C₆H₁₂O₆ + 6O₂

The light energy is captured and stored as chemical energy in glucose. This is why these organisms are the base of every food chain and are called producers (or autotrophs).

Step 3: Go through the options

• A. Consumer: Consumers (herbivores, carnivores, omnivores) cannot make their own food. They get energy by eating other organisms.
• B. Producer: Producers make their own food by photosynthesis, so they change light energy into chemical energy. ✔
• C. Decomposer: Decomposers (bacteria and fungi) break down dead organic matter and release nutrients back into the soil. They do not trap light energy.
• D. Carnivore: This is a type of consumer that feeds on other animals, so it is not the answer.

Step 4: Answer The correct option is B. Producer.

Exam tip: Link the words to their roles: Producers = Photosynthesis = Plants. When a question mentions "light energy" or "making food", think producer. When it mentions "feeding on others", think consumer. When it mentions "breaking down dead matter", think decomposer.