RAS question
A food web differs from a food chain because:
Correct answer: (B) A food web shows interconnected food chains.
A food web differs from a food chain because it shows interconnected food chains in an ecosystem, not a single linear pathway of energy flow.
Explanation
A food chain presents one linear route by which matter and energy pass from one organism to another. A food web is wider: it shows how food chains interconnect and overlap within an ecosystem. That is why option B is the precise distinction. Britannica describes a food web as a complex network of interconnecting and overlapping food chains and notes that it shows how food chains intertwine in an ecosystem. This also explains why the idea is more realistic than a single chain: most organisms consume, or are consumed by, more than one species, so their feeding relationships cannot usually be represented by only one path.
Why the other options are wrong
- (A) A single path describes a food chain, whereas a food web contains multiple interconnected feeding paths.
- (C) They are not the same because a food chain is linear, while a food web represents overlapping and interconnected food chains.
- (D) A food web does not ignore producers; producers are part of food webs and form the base of food-energy structure in an ecosystem.
Concept
This tests ecosystem energy flow, especially the distinction between food chains and food webs. It recurs in RAS because ecology questions often check whether candidates understand real ecosystem interdependence rather than memorising isolated terms.