Trophic Levels

• Trophic level 1: Plants and algae make their own food and are called producers
• Trophic level 2: Herbivores eat plants/algae and are called primary consumers
• Trophic level 3: Carnivores that eat herbivores are called secondary consumers
• Tropic level 4: Carnivores that eat other carnivores are called tertiary consumers. Apex predators are carnivores with no predators
• Decomposers break down dead plant and animal matter by secreting enzymes into the environment and then small soluble food molecules diffuse into the microorganism
• Pyramids of biomass can be constructed to represent the relative amount of biomass in each level of a food chain
• Trophic level 1 is at the bottom of the pyramid

  
• Producers are mostly plants and algae which transfer about 1% of the incident energy from light for photosynthesis
• Only approximately 10% of the biomass from each trophic level is transferred to the level above it
• Losses of biomass are due to

  • Not all the ingested material is absorbed, some is egested as faeces
  • Some absorbed material is lost as waste, such as carbon dioxide and water in respiration and water and urea in urine
• Large amounts of glucose are used in respiration