Types of microorganisms | Their Examples with Pictures

Microorganisms are living beings that are not visible to the naked eye.

They can be viewed only with the help of a microscope.

In spite of their minute size, they carry out their body functions and physiology independently like higher animals.

These organisms are mostly single-cellular, and very few are multi-cellular.

The differences among microbes can be learned based on their structure, physiology, habitats, and food habits.

Types of Microorganisms

1. Bacteria
2. Archaea
3. Algae
4. Fungi
5. Protozoa
6. Yeast
7. Diatoms
8.  Virus

Bacteria

• These are said to be the first organisms to have appeared and are single-cellular.

• The cell has a cell wall and may also have a flagella.

• They are called “prokaryotic cells” because they lack a clear-cut nucleus.

• Bacteria are omnipresent, i.e., they can be found on the earth’s surface, underneath, in the air, in the living bodies, etc.

• They obtain their food by different means like parasitic nature, saprophytic, symbiotic methods, etc. 

• They eat up almost anything, leading to the decay of any waste.

• Bacteria cause many diseases like tuberculosis, leprosy, cholera, etc.

Archaea

• These are similar to bacteria but live in more harsh conditions and extreme temperatures.

• They differ from bacteria in a few biochemical molecules.

Algae

• These are multi-cellular yet microscopic in nature.

• They can be seen when they grow in large colonies as patches.

• They live in marine and also freshwater environments.

Ex: Spirogyra.

Fungi

• These are multi-cellular; some are microscopic, while others are macroscopic.

• They grow on bread and other foodstuffs at home or in eateries.

• They can be invisible when present as single strands.

• But as they grow into many strands, they can be visible as fluffy material.

Ex: Rhizopus.

• Fungi cause topical infections like ringworm and deranged nails on toes.

• They can also cause internal infection.

• But there are a few important uses of fungi.

Protozoa

• These are a large class of animals that are visible only under a microscope.

• They have the ability to move and find their food.

• They can cause diseases in man and other large animals. They are mostly found in fresh water and in slimy, moist soil.

Ex: Amoeba.

• You can read more about them in the examples of protozoa.

• Diseases caused by protozoa include malaria, gingivitis, etc.

• These are examples of single-celled parasites.

Yeast

• These are classes of fungi but are single-celled.

• They are some of the widely used organisms for human purposes, such as the production of alcohol, baking as nutritional supplements, etc.

Diatoms

• These are a type of microalgae enclosed in the cell wall made of silica.

• They are mostly present in fresh water and marine water.

Virus

• These are not living organisms, so they cannot be called microbes.

• But this virus is a biological agent that takes up host nuclear machinery and multiplies upon entering into living beings.

• They are absolute parasites and cannot live without a host.

• They have a protein coat and nucleic acid-like DNA or RNA.

• They cause many types of diseases in plants and animals.