Energy flow
The Sun is the original source of energy for almost all organisms on the Earth. The way energy passes through an ecosystem is described as energy flow.
Plants trap sunlight energy in chlorophyllThe green chemical inside the chloroplasts of plant cells. It enables photosynthesis to take place. and use it in photosynthesisChemical reaction that happens in plant cells. It converts carbon dioxide and water into glucose and oxygen in the presence of light. The glucose can then be used for a number of processes including growth. to make food (sugar and starch) that can be passed onto animals.
Animals/consumer An animal that eats a plant or another animal in order to obtain energy. obtain the food made by plants/producers through feeding.
Herbivores (plant eating animals) are primary consumers.
Carnivores (animals who eat other animals) are secondary consumers while those that feed on secondary consumers are tertiary consumers.
This sequence of feeding (producers, primary consumers, secondary consumers and tertiary consumers) shows the flow of energy.
The different stages in the feeding sequence are also referred to as trophic levels. Producers are trophic level 1; primary consumers are trophic level 2 and so on.