Why we say energy flow in the biosphere is unidirectional?
Answers
ANSWER :
The energy flow through different steps in the food chain is unidirectional. This means that energy captured by autotrophs does not revert back to the solar input and it passes to the herbivores, i.e. it moves progressively through various trophic levels. Thus, energy flow from the sun through producers to consumers is in single direction only.
Answer:
In a food chain, along with food, transfer of energy also occurs from one trophic level to the other. The flow of energy which occurs along a food chain is called energy flow.
Due to the loss of energy at each step, food chains consist of only three to four trophic levels. If there are many levels, then animals at the end of the food chain will not have enough food and energy to survive.
The solar energy converted by the autotrophs into food energy cannot be reconverted into solar energy, and the energy which passes from the herbivores to the carnivores can never go back to the herbivores. The energy lost as heat cannot be returned to the plants and reused during photosynthesis.
Therefore, the flow of energy through a food chain is always unidirectional.