In the diagram above, the water in the two beakers has been heated by the same Bunsen burner for the same amount of time. This means that the same amount of energy is transferred to both.

It can be represented on an energy level diagram. The diagram shows that when a catalyst is used, the activation energy is reduced. This makes more of the collisions successful at a given temperature.

Each food chain is a descriptive diagram including a series of arrows, each pointing from one species to another, representing the flow of food energy from one feeding group of organisms to another.