Concept: Trophic Levels

One concept that I have to understand is the idea of trophic levels in environmental science. The trophic level of an organism refers to the organisms place in the food chain. Organisms at the bottom of the food chain such as green plants are called producers because they produce their own energy, while tertiary consumers are on the top of the food chain and obtain energy by feeding on other organisms that are also predatory themselves thus depending on the existence of all the organisms at the lower levels. At each trophic level energy and nutrients are transferred but the energy that a primary consumer recieves from a producer is not equal to the amount of stored energy in that organism. Likewise, with the transfer of energy from any level to the next there is always a loss of energy, this means that at higher trophic levels less organisms can exist.