Energy Transfer

Question 1

What does a Pyramid of Numbers show?

Answer 1

• Shows the abundance of each specie at each trophic level of the food chain
• Producers are the smallest but feed many primary producers
• Secondary consumers are also large but tertiary consumers are rare

Question 2

What does a Pyramid of Biomass show?

Answer 2

• Measures the exact biological mass at each level.

- Each trophic has less biomass than the previous one, as energy is lost not all transferred

Question 3

What does a Pyramid of Energy show?

Answer 3

• Shows energy transferred to each trophic level
• Only a small amount of biomass is available to the next trophic, since it is wasted as:
  
  • Heat (respiration)
  • Faeces/urine
  • Undigested biomass (chemical energy)

Question 4

Why are large predators rare?

Answer 4

The quantity of energy that is transferred out of the food chain between each trophic level. There is a limit to the number of levels an ecosystem can support.
The vast amount of light energy that was trapped by producers isn’t available as chemical energy to predators.

Question 5

Equation for efficiency of energy transfer?

Answer 5

Total energy supplied to organism