Open In App

Difference Between Unicellular And Multicellular Organisms

Last Updated : 27 Feb, 2023
Comments
Improve
Suggest changes
Like Article
Like
Report

Every living organism on this planet is made up of cells, and these cells help in the proper functioning of this living organism. There can be one or more cells in a living organism, and an organism with a single cell is known as a unicellular organism, while on the other hand, organisms with multiple cells are known as multicellular organisms. 

What is a Unicellular Organism?

A unicellular organism or commonly referred to as a single-celled organism is an organism made up of a single cell and these organisms rely on this single cell for all their functionality. These unicellular organisms are further divided into two categories i.e. eukaryotic and prokaryotic. Eukaryotic are multicellular organisms whose cell contains the nucleus and other organelles, while on the other hand, most prokaryotic are unicellular in which the nucleus is absent. These unicellular organisms are considered to be the oldest living organisms, whose occurrence dates around 4 billion years ago. Amoeba, plasmodium, euglena, algae, protozoa, paramecium, and fungi are some of the common unicellular organisms.

What is a Multicellular Organism?

Just opposite to unicellular or single-celled organisms, multicellular organisms are one that contains multiple cells, which work together to achieve the proper functionality in that living organism. In Multicellular organisms, different cells are responsible for different tasks. Almost all species of land plants and animals are multicellular, however, some plants and bacteria can be partially multicellular as well. These multicellular organisms are the result of cell division or a combination of cells. Humans, dogs, cows, cats, trees, chickens, and other animals are examples of multicellular organisms.

Difference Between Multicellular and Unicellular Organisms?

Unicellular Organisms

Multicellular Organisms

Made up of a single cellMade up of a combination of multiple cells
The whole cell is exposed to the outer environmentOnly outer cells are in contact with the environment
It usually has a shorter lifespanIt has a longer lifespan
The body formation is quite simpleThe body formation is quite complex in nature
Both eukaryotes and prokaryotes fall into this categoryOnly eukaryotes come under this category
The whole life process is controlled by a single cellMultiple cells together are responsible for proper functioning
These species are microscopic in natureMost of these organisms are macroscopic in nature
Unicellular organisms can be either autotrophs or heterotrophsMulticellular organisms are both autotrophs and heterotrophs
Any serious injury to a cell can lead to deathAny physical damage to a cell doesn't lead to death
Bacteria, yeast, amoeba, and paramecium falls under unicellular organisms.Humans, plants, animals, and birds fall under multicellular organisms.

Conclusion

Both unicellular and multicellular organisms have different body structures the unicellular organisms are more prone to extreme temperatures and are thus often called extremophiles. Unicellular organisms can sustain extremely cold to extremely hot temperatures. While on the other hand, normally multicellular organisms can resist extreme temperatures. For example, a small injury or physical damage to a multicellular organism doesn't lead to death but can surely lead to death in unicellular organisms. Apart from body construction, unicellular organisms rely upon a single cell for whole-body functions, while multicellular organisms rely on multiple cells. 


Next Article

Similar Reads

  翻译: