Food Chain - GCSE Geography Definition

A food chain is a sequence that shows how energy and nutrients flow through an ecosystem, from one living thing to another. It begins with plants, which use sunlight to make their own food. These plants are eaten by herbivores, or plant-eaters. Next, carnivores, or meat-eaters, consume the herbivores. Each link in the chain represents a different level of this energy transfer, called a "trophic level." Decomposers, like bacteria and fungi, play a vital role at the end of the chain by breaking down dead plants and animals, returning nutrients to the soil, and allowing the cycle to start again. Understanding food chains helps us see how all living things are interdependent and how energy is passed along within ecosystems.