1-Ecologists call this one-way flow of matter and energy from a producer to a primary, then to secondary, and perhaps to a tertiary consumer, a food chain. The food web shows all the organisms at each feeding level or trophic level.
2-Energy flows through an ecosystem in one direction: from producer to primary consumer to secondary consumer to higher consumers. A biomass pyramid provides a picture of the feeding and energy relationships within a food web and the direction of the flow of energy.
