Unicellular vs Multicellular Organisms

What are Unicellular Organisms?

Unicellular organisms are organisms that consist of only one cell. Their main purpose is to carry all the necessary functions of life, such as respiration, digestion, reproduction, metabolism, and help maintain homeostasis.

Some example of unicellular organisms are:

• Bacteria

• Protista

• Diatoms

• Protozoa

Unicellular organisms have bacteria, yeast, and protists. They can be both, eukaryotic or prokaryotic cells, which means that they can have a nucleus and other organelles, or not have any.

What are Multicellular Organisms?

Multicellular organisms are organisms that consist of more than one cell  (30-40 trillion), categorized into groups that take on different functions. Their purpose is to take in nutrients, utilize energy, remove unwanted waste, and interact with the environment.

Here are some examples of multicellular organisms:

• Humans

• Animals (eg: cats, dogs)

• Plants (eg: trees)

• Fungi (eg: mushrooms)

What is the key difference between unicellular and multicellular organisms?

The main difference between unicellular and multicellular organisms is their cell structure and complexity.  Unicellular organisms are generally only made up of one cell that performs all life's necessary functions, whereas multicellular organisms  include several cell groups, These groups take on different specialized tasks.