Question

in a given ecosystem, producers convert solar energy into 15,000 kcal of chemical energy stored in organic compounds. which of the following is the most likely amount of energy available to secondary consumers?
a 1.5 kcal
b 150 kcal
c 1,500 kcal
d 13,500 kcal

Explanation:

Step1: Recall energy - transfer rule

In an ecosystem, about 10% of energy is transferred from one trophic level to the next. Producers are at the first - trophic level and secondary consumers are at the third trophic level.

Step2: Calculate energy available to primary consumers

If producers have 15000 kcal of energy, the energy available to primary consumers (first - level consumers) is 10% of 15000 kcal, which is $0.1\times15000 = 1500$ kcal.

Step3: Calculate energy available to secondary consumers

The energy available to secondary consumers is 10% of the energy available to primary consumers. So it is $0.1\times1500=150$ kcal.

Answer:

B. 150 kcal