Answer:
B. 10
Explanation:
The percentage of energy transferred from one trophic level to the next varies between 5% and 20% and
is called the ecological efficiency (efficiency of energy transfer). An average figure of 10% is often used.
The ten percent law states that the total energy content of a trophic level in an ecosystem is only about
one-tenth (or 10%) that of the preceding level
EXAMPLE: if the grasses produce 1000 kcal of energy, how many kcal are theoretically available to the frogs?
When energy is passed in an ecosystem from one trophic level to the next, only ten percent (10%) of the energy will be passed on. We can consider a typical food chain in the environment. It can be written as follows. Sun -----> Green Plants -----> Insects -----> Frogs -----> Snakes. The sun provides the energy that is used by the green plants. The green plants are the primary producers for the food chain. The energy from the sun is converted by the plants into food. The insects are the primary consumers. They are the first animals to eat the plants. When they eat the plants and obtain some of the energy (10%) they stored when making food. The rest of the energy is lost and dissipated as heat. Insects are eaten by frogs. The frogs are the secondary consumers in this food chain. They obtain part of the energy stored by the insects. The remaining energy stored by the insects is lost
