Microorganisms+ Infectious Diseases

By: Ethan Needham

8.L.1.1 Summarize the basic characteristics of viruses, bacteria, fungi, and parasites relating to the spread, treatment and prevention of disease.

8.L.1.2 Explain the difference between epidemic and pandemic as it relates to the spread, treatment and prevention of disease.

What is Microbiology?

Microbiology is the branch of science that deals with micro organisms such as bacteria, viruses, parasites and fungi.

Micro Organisms

Micro organisms are life forms two tiny to see with the naked eye and are many different shape sizes and color. Some our helpful towards humans but many can be harmful as well. Today we will be talking about 4 micro organisms and what illnesses they can cause.


Viruses are non-living micro organisms. A virus can only be harmful when inside the body. When a virus attacks it attaches on to an healthy cell then makes copy's of itself. When there are too many copy's the cell bursts and the cycle continues. Viral diseases can be prevented with vaccines. Different viruses cause different illnesses and symptoms. Viruses also range in different shapes and sizes but something they all have in common would be for example a capsid located in the head reign.


Bacteria are living micro organisms. Bacteria may be spear like, rod like, or spiral like. These are the shapes that they may come in. They also range in size and color. Bacteria is every where on the planet, even places you might not think. New bacteria life forms are being discovered every day. Scientist have recently discovered one that can withstand a million degrees. They also multiply at very fast rates. Most of these are harmless but you will find some however that can really cause some damage. For example Salmonella is a type of food poisoning caused by Enterica bacterium. Ways that can stop bacteria from further damage is through antibiotics.


Fungi is a living multi celled micro organism. Fungi comes in a lot of shapes and sizes. Mold, Mildew, yeast and mushrooms are all examples of Fungi. Some fungi such as certain mushrooms are harmless and even edible. But others are not. Athletes foot for example is not helpful in any way. The fungus on your feet grows in warm and damp conditions. It makes your foot itchy and green in some cases. Fungi can also cause worse diseases such as Aspergillus which can cause fever and headache, coughing up blood, nosebleed, and chest and joint pain and if not treated death. Fungus or fungi takes nutrients from dead or living substances and uses them too grow.


Parasites are living micro organisms. They range in sizes from microscopic like dust mites or as big as a mosquito. They take nutrients from there host and in the process may transfer a disease. Such as a mosquito, they suck up blood from there victim and can leave disease such as malaria. Different parasites can cause different diseases.