What is the main function of producers in an ecosystem?

Producers play a crucial role in an ecosystem by converting sunlight into energy through the process of photosynthesis. This process involves plants, algae, and some bacteria utilizing sunlight, along with water and carbon dioxide, to create glucose, which serves as a source of energy for them. In doing so, they produce oxygen as a byproduct, which is essential for the survival of most living organisms.

This energy conversion is vital for the entire food chain; producers form the foundation upon which all other trophic levels depend. Herbivores, which consume these producers, derive their energy from them, and subsequently, carnivores consume the herbivores. Without producers capturing and converting solar energy, the entire ecosystem would collapse, as energy would not flow through the food web.

In contrast, the other options relate to different functional roles within an ecosystem. Decomposers break down dead organic matter, consumers rely on producers for energy, and while nutrient cycling is essential for ecosystem health, it is not the primary function of producers. Their unique ability to harness solar energy makes them indispensable to ecological balance.