Pick out the incorrect statements with respect to the energy flow.

1. The flow of energy is unidirectional.
2. The flow of energy is bidirectional.
3. The energy available at each level gets reduced progressively.
4. The energy available at each level gets increases progressively.

From the energy flow, two statements are very important. Firstly the energy flow is unidirectional. As it moves progressively through the levels, it is no longer available to the previous level. Secondly, the energy level available at each trophic level gets diminished progressively due to the loss of energy at each level.