Types of Microorganisms

Microorganisms are divided into five major categories:- 

Fungi, Bacteria, Viruses, Algae and Protozoa.

Fungi:- 

Fungi (fungus) are plant like microorganisms that do not have chlorophyll. Hence they are non green. Fungi can be unicellular such as yeasts or multi cellular organisms such as moulds. They are mostly found in warm and moist places. 

Bacteria:- 

Bacteria are the smallest and the oldest known unicellular organisms on our planet. Although bacteria are mostly present as single celled microorganisms but sometimes they live in group s called colonies. They can be found almost everywhere such as air, water and even food. Some bacteria are useful while some can be every harmful. Harmful bacteria when enter our body through air or water cause diseases like cholera and typhoid. 

Algae:- 

Algae are the plant like microorganisms. They can exist as the unicellular or multi cellular organisms. They contain cell and chlorophyll. Due to the presence of chlorophyll they can photosynthesize. Some algae have color pigments like green and blue. Therefore based on the color of the pigment present in the algae they can be classified into different categories such as green algae, blue algae and blue green algae.

Protozoa:- 

Unlike other microorganisms we discussed so far protozoa are the unicellular microorganisms that have animal like characteristics. They can move from one place to another and can hunt their food. They are mostly aquatic but can also be found in soil and the bodies of other organisms. Such protozoa that live in the bodies of other organisms are called parasites. 

Viruses:- 

Viruses are one of the smallest microorganisms. They are so small that they cannot be seen even through an ordinary compound microscope. The name virus is derived from a Latin word meaning “poison” to observe virus’s special microscopes called electron microscopes are used.