What are the differences between food chains and food webs?

A food chain represents the pathway of the transfer of food and energy in an ecosystem through different organisms. There is only a single pathway in a food chain, which means that an organism is dependent on the organism on the lower trophic level for food and energy (for example, deer is dependent on grass) and cannot get its energy elsewhere. In comparison, a food web consists of a number of interconnected food chains and thus, each organism is part of a number of food chains. This results in multiple pathways for transfer of food and energy and ensures that each organism can receive food and energy from different organisms. 

A food chain is very simple, while a food web is complex. Also, the removal of organisms at any trophic level will destroy the food chain, whereas the same is not true for a food web, since organisms are a part of different interconnected food chains. 

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