A food web is similar to a food chain but larger,and it is a diagram that combines many food chains into one picture.
For example, a tree produces acorns - this is called the producer. Mice, squirrels, and insects eat these acorns and because there are many mice, the weasels, snakes and raccoons have food. With insects in the acorns, other predators would be attracted (like skunks or opossums) and therefore, foxes, hawks or owls could all find food. Food webs can be effected in many ways considering the urban areas of major countries are taking no action and care. It uses arrows to show the energy relationships among organisms A food chain is a linear sequence of organisms through which nutrients and energy pass as one organism eats another. Let's look at the parts of a typical food chain, starting from the bottom—the producers—and moving upward.
At the base of the food chain lie the primary producers. The primary producers are autotrophs and are most often photosynthetic organisms such as plants, algae, or cyanobacteria. The organisms that eat the primary producers are called primary consumers. Primary consumers are usually herbivores, plant-eaters, though they may be algae eaters or bacteria eaters. The organisms that eat the primary consumers are called secondary consumers. Secondary consumers are generally meat-eaters—carnivores. The organisms that eat the secondary consumers are called tertiary consumers. These are carnivore-eating carnivores, like eagles or big fish. Some food chains have additional levels, such as quaternary consumers—carnivores that eat tertiary consumers. Organisms at the very top of a food chain are called apex consumers.