Heres one of my favorites. We have food webs,food chains, and an energy pyramid. So you are probably thinking well isnt a food web and food chains the same thing, well if you are then you are WRONG! Food webs are a diagram that shows the feeding relationships between organisms in an ecoysystem and a food chain is the pathway of energy trasnfer through various stages as a result of the feeding patterns of a series of organisms. So thats how they are different. Now your probably thinking how can you tell them apart, well the picture on the left is a food web and the one under it is a food chain. Sometimes its confusing to usde a web or chain but its really easy to.
So on a food chain you have to have the producer(orgainsms that use sunlight to make their own food),consumers( organisms that eat other organisms) and Decomposers( organisms that get energy by breaking down dead organisms). There are also three types of consumers that you need to know: herbivore(an organism that eats only plants),carnivore( an organsim that eats animals), and omnivore(an organsim that eats both plants and animals).The top level on a food chain is called the tertiery and the lowest is the prducer.
The last one is the energy pyramid. an energy pyramid is a traingular diagram that shows an ecosystems loss of energy which results as energy passes through the ecosystems food chain. The energy at each level of a food chain is the same as a energy pyramid, In the energy pryamids you have the producer and then the consumers and then the top consumers which are the tertiary. A energy pyramis has a big bottom for the producers and the top is small becasue less energy is stored at the highest levels then the lowest levels.