Food Chains
A food chain is defined as the sequence of organisms feeding on each other in an ecosystem. Organisms are classified according to their place in the food chain. A herbivore is always referred to as a first order consumer. An animal feeding on the herbivore is the second-order consumer, the animal feeding on the second-order consumer is the third-order consumer and so forth. The first order-consumer feeds on producers (plants). An animal that eats another animal is know as the carnivore. A food chain is always written across the page.
Food Web
Food webs are an interconnection of many food chains in the one ecosystem. Food webs are always written up the page.
Pyramids of Biomass
Pyramids of biomass are diagrams which show the total mass of organism at each stage in the food chain.