LIFE SCIENCE

Detailed explanation-1: -Energy flows in one direction from lower to higher levels. It will never return to lower levels, and as it moves up one level from lower levels, it always loses energy.

Detailed explanation-2: -The flow of energy in the ecosystem is unidirectional because the energy lost as heat from the living organisms of a food chain cannot be reused by plants in photosynthesis. During the transfer of energy through successive trophic levels in an ecosystem, there is a loss of energy all along the path.

Detailed explanation-3: -In an ecosystem, the flow of energy is said to be one way because it passes on from one organism to another in a food chain but never comes back. Plants directly use energy from the sun to make food via the process of photosynthesis.