pyramids of biomass

• What do pyramids of biomass represent?


  The relative amount of biomass at each level of a food chain
• What is found at trophic level 1 of a pyramid of biomass?


  Producers, such as plants and algae
• Why do producers have the largest biomass in a pyramid of biomass?


  Because they generate their own food via photosynthesis
• What are the types of consumers found in a pyramid of biomass?

  Primary consumers, secondary consumers, and tertiary consumers
• What does the shape of the pyramid of biomass indicate?


  How energy and biomass are transferred through the ecosystem
• What should students be able to do according to WS 1.2?


  Construct accurate pyramids of biomass from given data
• What percentage of incident energy do producers transfer during photosynthesis?


  About 1%
• How much biomass is transferred from each trophic level to the level above it?


  Approximately 10%
• If a primary consumer eats a producer, what percentage of the producer's biomass is transferred to the consumer?


  10%
• Why does biomass decrease as you move up trophic levels?


  Not all ingested material is absorbed and energy is lost through respiration and excretion
• What is egestion in the context of biomass loss?


  Material that is excreted as waste (faeces)
• What happens to absorbed material in terms of biomass loss?


  It is used for processes other than growth, such as respiration and excretion
• What is the formula to calculate the efficiency of biomass transfer?

  $\text{Efficiency} =$$\left( \frac{\text{Biomass at higher trophic level}}{\text{Biomass at lower trophic level}} \right) \times 100$
• What is the 10% Rule in the context of biomass transfer?


  On average, only 10% of the biomass at one trophic level is available to the next
• Why are there fewer organisms at higher trophic levels?


  Due to the loss of biomass and energy transfer inefficiencies
• What is an apex predator?


  The top of the food chain with no predators
• What should students be able to do according to MS 1c?


  Calculate the efficiency of biomass transfer and explain its effects