The yellow perch, in turn, are eaten by walleyes, bass, pike, and muskies. The gamefish may then be caught and eaten by a lucky angler. A meal of fresh fish provides both energy and nutrients for the angler. That energy was produced by the photosynthetic phytoplankton and cycled through the zooplankton, yellow perch, and gamefish to the angler. The term food chain is used to describe the movement of energy and nutrients through a series of plants and animals in an ecosystem.
All food chains begin with photosynthetic green plants or producers .
Animals feeding on green plants are called primary consumers . At the next level of the food chain are secondary consumers which feed on the primary consumers. There may be a third, fourth, or fifth level of consumers in a food chain. These nutrients are absorbed by green plants and recycled through another food chain. Most organisms feed on a wide variety of plants and animals.