If producers generate 100% of the energy, what percentage of that energy is left by the time it reaches tertiary consumers?
a. 1%
b. 0.1%
c. 100%
d. 10%
To answer this question, we need to understand the concept of energy transfer in an ecosystem. The energy flow in an ecosystem is represented by a pyramid-shaped model called the energy pyramid.
At the base of the energy pyramid are the producers, such as plants or algae, which convert sunlight into energy through the process of photosynthesis. Producers generate 100% of the energy in an ecosystem.
Moving up the pyramid, the energy is transferred to primary consumers, which are herbivores that feed on the producers. Primary consumers obtain energy by consuming plants and algae.
The energy is then transferred to secondary consumers, which are carnivores that feed on the primary consumers. Secondary consumers obtain energy by consuming herbivores.
Finally, tertiary consumers are at the top of the energy pyramid, and they are carnivores that feed on other carnivores. Tertiary consumers obtain energy by consuming secondary consumers.
As energy moves up the energy pyramid, only a fraction of the energy is transferred from one trophic level to the next. This is because some energy is lost as heat during metabolic processes, or it is used by organisms for growth, reproduction, and other activities.
On average, each trophic level receives about 10% of the energy from the level below it. This phenomenon is known as the 10% rule.
So, when the producers generate 100% of the energy, only about 10% of that energy is transferred to the primary consumers, then 10% of that energy is transferred to the secondary consumers, and finally, around 10% of the energy reaches the tertiary consumers.
Therefore, the correct answer is:
d. 10%