Hello. This question is incomplete. The full question is:
"Which of the following is true about the flow of energy within ecosystems? A. Energy flows from living systems into the physical environment only. B. Energy flows both ways between living systems and the physical environment. C. Energy flows from the physical environment into living systems only. D. Energy does not flow between living systems and the physical environment."
Answer:
B. Energy flows both ways between living systems and the physical environment.
Step-by-step explanation:
Energy lives in a constant flow within ecosystems. This energy flows in both directions between living systems and the physical environment.
An important aspect to understand the transfer of energy within an ecosystem is the understanding of the first fundamental law of thermodynamics that says: "Energy cannot be created or destroyed, but transformed". As an illustrative example of this condition, we can mention sunlight, which as a source of energy, can be transformed into work, heat or food depending on photosynthetic activity; but in no way can it be destroyed or created.
Another important aspect is the fact that the amount of energy available decreases as it is transferred from one trophic level to another. Thus, in the examples given above of food chains, the grasshopper obtains, by eating the leaves of the tree, chemical energy; however, this energy is much less than the solar energy received by the plant. This loss in transfers occurs successively until the decomposers are reached.