Question

The flow of energy is always _______ in food chains.

Answer 1

Characteristics of food chain:

1. A food chain is always straight and proceeds in a progressive straight line.

2. In a food chain, there is unidirectional flow of energy from sun to producers and subsequently to series of different types of consumers.

3. Usually there occur 4 or 5 trophic levels in the food chain.

4. Generally 80-90% of energy is lost as heat at each transfer in accordance with second law of thermodynamics.

5. Some organisms occupy different trophic positions in different food chains.

So, the correct answer is 'Unidirectional'.