Saturday, January 3, 2009

How do energy and nutrients flow through an ecosystem?

An ecosystem is made up of producers, consumers and decomposers.

Energy and nutrients are transferred from producers to consumers to decomposers through feeding.


  • Energy from the sun/light energy is converted by producers into chemical energy and stored as food during photosynthesis.

  • Producers are mainly green plants.

  • Producers are are the only organisms that can manufacture or produce complex organic food from inorganic raw materials.

  • Thus, producers either directly or indirectly affect the lives of other organisms because they provide both energy and oxygen.


  • Energy is obtained their energy by feeding on other organisms.

  • Thus, all animals are consumers.

  • Herbivores (plant-eaters) feed directly on plants, hence they are only known as primary consumers.

  • Carnivores that feed on herbivores are know as secondary consumers.

  • Carnivores that feed on other carnivores are tertiary consumers.


  • Decomposers obtain their energy bu breaking down dead organisms, faeces and excretory products. (When dead organisms and waste matter are broken down, the materials lcoked up in them are released.)

  • These materials, such as inorganic nutrients, carbon and nitrogen compounds, are returned to the physical environment and are used again by green plants.

No comments:

Post a Comment