1. Microorganisms

2. Microorganisms-Bacteria

3. Bacteria
Bacteria belong to either kingdom Eubacteria or Kingdom Achaebacteria.
Some bacteria are decomposers and break down organic matter so it can be used again by other organisms.
They also play an important role in the nitrogen cycle. Bacteria fix nitrogen from the atmosphere to the found by changing ammonia into nitrite and nitrate, all containing nitrogen. Bacteria also return nitrogen from the soil to the atmosphere.
Bacteria can serve as food for small organisms.
Some live in the intestines of many organisms and help with the digestion of the large food molecules.
Bacteria can kill or make organisms sic, and they can spoinl food

4. Microorganisms-Virus

5. Virus
Viruses are not living organisms, unless they are inside a host cell. They do not need energy, move or reproduce on their own. Once they are attached to the host cell, they inject their DNA genetic information inside the cell and control the cell. The host cell will produce many new viruses.
Viruses are usually the cause of many diseases however they can also be used to study genetics and change characteristics of certain organisms.

6. Microorganisms-Fungi

7. Fungi
Kingdom Fungi contain organisms that are decomposers and break down dead organic matter.
They are food for other organisms and can be used to fight diseases.
They can spoil food, clothing and wood.

8. Microorganisms-Protists
Algae and phytoplankton
Protozoans and zooplankton

9. Protists
They belong to the kingdom Protista. There are tow major groups of protists: Animal-like (protozoans and zooplankton) and plant-like (algae and phytoplankton)
Plant-like protists act like plants, use photosynthesis to produce oxygen and food for other organisms.
Animal-like protists act like miniature animals as they must consume something else to obtain energy; they are food for larger organisms but can carry diseases affecting organism including humans