Bacteria vs. Viruses

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Bacteria: Most bacteria are very good. Only a few cause disease. Taking drugs called antibiotics can kill bacteria. However, due to misuse and overuse of antibiotics, bacteria today are more resistant to these drugs and are harder to kill. TB, for example, now affects 1/3 of the world population.


Fun Facts about Bacteria

Bacteria help our bodies with digestion and produce needed vitamins. Bacteria also help us by destroying harmful organisms within our bodies.

There are more bacterial cells in your body than there are human cells.

Most bacteria reproduce using a process called "binary fission." To do this, a single bacterium will grow to twice its normal size and then split into two "daughter" cells. The two new cells are exact copies of the original bacterium.

Bacteria are used to make cheese, milk, sourdough bread and yogurt.

99% of all bacteria are helpful.

Dead or weakened bacteria and viruses are used for making helpful vaccines.

Scientists estimate that bacteria produce nearly half the oxygen found in the atmosphere.

Helpful bacteria are used to purify water at sewage treatment plants and to break down oil after oil spills.

One healthy bacterium, given the proper environment, could reproduce into a colony of more than 2 million in just seven hours.

There are more microbes on your body than there are humans on the entire planet.

An area of skin as small as 6.5 square cm (1 square inch) may be home to more than half a million microbes.


Three groups:

1) Cocci = rounded

2) bacilli = rod shaped           

3) spirilla = spirals


The following is a fun and happy list of some different kinds of bacteria:


Rod Shaped






E. Coli







Scarlet fever



rheumatic fever



Plague, Black Death (bacillus) - lymph nodes become inflamed forming "buboes" Hence, the name bubonic plague.


Viral Diseases: Antibiotics do not work against the virus. Once you have a virus, you either fight it or die. Viruses are parasites. They are neither alive, nor dead. They cannot reproduce by themselves; they must force other cells to make progeny. The virus is made up of DNA or RNA surrounded by a protein coat. It takes over cells so that it can reproduce itself. The cell usually dies after reproduction. RNA viruses are not stable and therefore, they mutate often. Ebola is an RNA virus; this is why it can mutate so quickly. DNA viruses are more stable and therefore, they mutate less often.

The T-4 Bacteriophage virus is about to attack the bacterium.

The virus injects its genetic material into the bacterium.

The bacterium explodes after it is forced to make copies of the virus!


The following is a fun and happy list of some different viruses.

Smallpox - (Edward Jenner in 1796)

Poliomyelitis- (Jonas Salk, 1955)


Ebola Virus

Hanta Virus



Chicken pox

Common Cold







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