Food Chain & Food Web

Food Chain

Transfer of food energy from source (producer) to organisms consuming it (primary consumers) & further these organisms in turn are eaten up by organisms to which they are food source (secondary consumers) and so on, in a linear series.

Types of Food Chains:

• Grazing Food Chain:
  • Starts from living green plants (producers).
  • The producers are consumed by herbivores (primary consumers).
  • Further, herbivores are eaten up by carnivores (secondary consumers or primary carnivores) and so on.

• Detritus Food Chain:
  • Starts from dead/non-living organic matter, which is being broken down by microbes.
  • The organic matter is the then consumed by detrivores (primary consumers).
  • Detrivores are further eaten up secondary consumers or primary carnivores & so on.

In real life, it is impossible to consider each food chain as an isolated unit. Different food chains are interconnected making a sort of web termed food web.

Food Web

A food web contains a series of interconnected food chains.

Some other points to consider:

1. In all ecosystems, grazing & detritus food chains interconnected.
2. Assimilation of whole food consumed does not occur. Some undigested matter /faeces are diverted to detritus food chain.
3. Both overgrazing & undergrazing are detrimental as decrease or increase in population of any trophic level will affect the dependent trophical levels.