A food web is similar to a food chain but larger. Its diagram combines many food chains into one picture. The diagram uses arrows to show the energy relationships among organisms. Food webs show how plants and animals are connected in many ways.
Some of the organic matter eaten by heterotrophs, such as sugars, provides energy. Autotrophs and heterotrophs come in all sizes, from microscopic to many tonnes – from cyanobacteria to giant redwoods, and from viruses to blue whales.