4.7

4.7 Explain why only about 10% of energy is transferred from one trophic level to the next

Causes of the losses

ü  100 kJ of grass energy eaten by the mouse, but only 10 kJ is to become part of the mouse because the mice use the energy for respiration.

ü  Not all 100 kJ is available to the mouse to start with. Mice cannot digest cellulose so plant cell wall cannot be digested. The energy is lost as faeces, undigested material.