Apart from plants and animals, microbes form a permanent biotic component in an ecosystem. While plants have been referred to as autotrophs and animals as heterotrophs, what are microbes referred to as ? How do the microbes fulfil their energy requirements ?

On the basis of nutrition living organisms are classified in to two parts namely autotrophs and heterotrophs, autotrophs are light synthesize autotrophs and chemical synthesize or autotrophs who synthesize light and heterotrophs who synthesize chemical, white heterotrophs are classified into paracites hunting or detritus etc.

Microbes are detrititious and get nutrition from dead organic mass. They are seen in plants and animals. Digestion occurs outside the cell in them.