♥ The producer organisms in an ecosystem are the green plants. They convert the sun's energy into chemical energy.
♥ The herbivores are the primary consumers. They take into their bodies the energy which has been stored by the producers.
♥ The secondary consumers are carnivores. They take into their bodies the energy which has been stored by the herbivores.
♥ Green plants are autotrophs. They use the energy of the sunlight to make their food.
♥ Animals are heterotrophs. They gain their energy by eating other organisms.
♥ Energy flows from the sun to the autotrophs and then from the autotrophs to the heterotrophs.
♥ A food chain
ends with the top carnivore. A food chain is never very long because the amount of energy
available for the consumers decreases along the food chain.
♥ Since most animals have a varied diet, a
food web will show more clearly how many different things an animal eats.
♥ All green plants compete with each other for sunlight, water and minerals. All animals which
eat the same thing are also in competition with each other.
♥ Decomposer organisms and scavengers help to re-cycle essential chemicals through the food web.