I don't know what it means by what is the energy flow in a food chain?

Question

i have to explain in my project what is the energy flow in a foood chain

Answer 1

*Food chains, also called , food networks and/or trophic networks, describe the feeding relationships between species within an ecosystem. Organisms are connected to the organisms they consume by arrows representing the direction of biomass transfer. It also shows you how the energy from the producer is given to the consumer.Typically a food chain or food web refers to a graph where only connections are recorded, and a food network or ecosystem network refers to a network where the connections are given weights representing the quantity of nutrients or energy being transferred.

*A food chain is the flow of energy from one organism to the next and to the next and to the next. Organisms in a food chain are grouped into trophic levels,based on how many links they are removed from the primary producers. Trophic levels may contain either a single species or a group of species that are presumed to share both predators and prey. They usually start with a primary producer and end with a carnivore.

For more:

http://en.wikipedia.org/wiki/Food_chain