Flow of energy in an ecosystem is always
(a) unidirectional
(b) bidirectional
(c) multi directional
(d) no specific direction
(a)
An ecosystem is a network of living beings related to the nonliving beings of their environment, interacting as a system. The energy enters the plants (autotrophs) through photosynthesis during the making of food. This energy is then passed on to other trophic levels in the food chain. The energy moves progressively through various trophic levels so, it may not be available to the previous level. This flow of energy is unidirectional.
Therefore option (A) is correct