Question

In the food chain given below, if the amount of energy available at the fourth trophic level is 5 kJ, what was the energy available at the producer level?

$Grass\to Grasshopper\to Frog\to Snake\to Hawk$

(a) 500 kJ (b) 50 kJ (c) 5000 kJ (d) 5 kJ

Answer 1

(c) 5,000 kJ

According to the 10 per cent law, only 10 per cent of the energy available in a trophic level is passed on to the next level. Hence, if the amount of energy available at the fourth trophic level is 5 kJ, the energy available at the producer level will be

5,000 kJ:

The flow of energy :

5000 → 500 → 50 → 5.