How is a food chain defined?

A food chain is defined as a linear sequence of organisms through which energy and nutrients flow. In this sequence, each organism is eaten by the next one in line, starting from a primary producer, such as plants or algae, which convert sunlight into energy through photosynthesis. The primary producers are consumed by primary consumers, followed by secondary consumers, and so on up the chain. This linear structure illustrates the direct feeding relationships between individuals in an ecosystem and emphasizes how energy is transferred from one trophic level to another.

While other concepts like food webs encompass a more complex and interconnected set of relationships and interactions among various species, the term "food chain" specifically refers to this straightforward, step-by-step pathway of energy transfer. Understanding food chains is fundamental to grasping broader ecological concepts, such as energy flow and nutrient cycling within ecosystems.