Which organisms convert light energy into chemical energy stored as sugars, forming the base of most ecosystems?

• A. Producer
• B. Consumer
• C. Decomposer
• D. System

Answer: (A)

Producers do this. They capture light energy and convert it into chemical energy stored in sugars through photosynthesis. Plants, algae, and some bacteria use light to drive reactions that combine carbon dioxide and water into organic molecules like glucose, storing energy in the bonds of those sugars. This stored energy becomes the foundation of most ecosystems because consumers rely on these organic molecules for energy and carbon, either directly by eating producers or indirectly by eating organisms that consumed producers. Decomposers recycle nutrients by breaking down organic matter but don’t initiate the energy capture from light, and a “system” is not an organism.