What is a Food Chain?

Answer 1

A food chain is a kind of ecological model. All ecological models seek to demonstrate the interrelationships between different kinds of organisms, but food chains focus only on those relationships that are evident in how an organism obtains sustenance.

A typical food chain will begin with the sun, which provides sustenance for photosynthetic plants. These plants are eaten by a first tier of grazers and seed-eaters, which are then eaten by a second tier of carnivores. The relationships can get very complex, however, as organisms do not often "eat" only one kind of food and are often eaten, or provide sustenance to, many other kinds of organism. Indeed, many organisms, such as plants and bacteria, don't eat in the same way as animals at all.

A proper food chain does not exactly have a "top". When we say that humans are at the top of the food chain, we forget that we provide sustenance for many organisms. Microorganisms and tiny arthopods feed on our bodies and our waste. Many animals, such as domestic livestock, are sustained by human efforts only to be eaten by humans. Humans also have many parasites and live alongside all manner of commensal organisms, organisms who eat our food (like rats).

Answer 2

there was an old lady who swallowed a fly. the lyrics of that song are a food chain.

Answer 3

Animal species eating each other in order of their superiority.
Humans are at the top of the chain. There is nothing in the world that eats us. Humans eat cattle, cattle eats grass.

Answer 4

A chart that describes what animal eats/has dominance over the other.

That was decribed in my own words, your better off getting your info from http://en.wikipedia.org/wiki/Food_chain