Trophic levels

• what does a food chain show?

  describes the feeding relationships between organisms and the resultant stages of biomass transfer
• what are trophic levels?

  stages in a food chain
• how are trophic levels represented?

  • numbers, starting from 1
  • after 1, numbered according to how far along the organism is in the food chain
• what is trophic level 1?

  plants and algae which make their own food through photosynthesis - producers
• what is trophic level 2?

  herbivores which eat producers - primary consumers
• what is trophic level 3?

  carnivores that eat herbivores - secondary consumers
• what is trophic level 4?

  carnivores that eat other carnivores - tertiary consumers
• what is an apex predator?


  carnivore with no predators
• how do decomposers break down dead matter?

  • release enzymes which catalyse the breakdown of dead material into smaller molecules
  • soluble small food molecules then diffuse into the microorganisms