Unicellular and Multicellular Organisms

 

1. There are many kinds of organisms in nature.

2. Organisms can be divided into two groups.

 

Organisms

Unicellular Organisms

- Unicellular organisms are organisms that consist of only one cell ('uni' means one).

- Unicellular organisms are microorganisms, they are very tiny and can only be seen under
    a microscops.

- Even though unicellular organisms are made up of one cell, they carry out life processes
   such as movement, responsem respiration, digestion, excretion, reproduction and growth.

- Examples of unicellular organisms:

Multicellular Organisms

- Multicellular organisms are organisms that consist of many cells ('multi' means many).

- Like unicellular organisms, multicellular organisms carry out all the life processes.

- Some multicellular organisms are made up of a few cells. They are too tiny to be seen
   with our naked eyes. They are microorganisms too.

- Other multicellular organisms are made up of millions of cells. (Figure 2.19)

- Each type of cell has a different structure and carries out specific functions.