Question

Study the picture given below showing three food chains (a), (b) and (c) and answer the following questions:

1. Name the type of ecosystems that exist in food chains (b) and (c).
2. The first trophic level in all food chains is producers. Why? What percentage of solar energy do these producers capture for their use?
3. Why are the arrows shown in the diagram in one direction only and not vice versa? Justify.

Answer 1

1. The ecosystem in food chain (b) is a terrestrial ecosystem, likely a forest or grassland, and the ecosystem in food chain (c) is a marine ecosystem.
2. The first trophic level in all food chains is producers because they can synthesize their own food from inorganic sources using light or chemical energy. Producers, primarily plants and algae, use photosynthesis to convert solar energy into chemical energy stored in carbohydrates. Typically, producers capture only about 1% of the available solar energy for their use.
3. The arrows in the diagram represent the flow of energy, which only moves in one direction: from the producers to the consumers. Energy is transferred when one organism consumes another. It is not reciprocal because when energy is transferred, some of it is lost as heat due to metabolic processes, thus it cannot move backwards. This is in accordance with the second law of thermodynamics.