Viruses and Bacteria

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Viruses and Bacteria

• By Brad Washburn

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What are Viruses?

• Viruses are too small to be seen by the naked
  eye. They can't multiply on their own, so they
  have to invade a 'host' cell and take over its
  machinery in order to be able to make more virus
  particles.

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What are Viruses? (continued)

• Viruses consist of genetic materials (DNA or RNA)
  surrounded by a protective coat of protein. They
  are capable of latching onto cells and getting
  inside them. The cells of the mucous membranes,
  such as those lining the respiratory passages
  that we breathe through, are particularly open to
  virus attacks because they are not covered by
  protective skin.

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What are Bacteria?

• Bacteria are organisms made up of just one cell.
  They are capable of multiplying by themselves, as
  they have the power to divide. Their shapes vary,
  and doctors use these characteristics to separate
  them into groups. Bacteria exist everywhere,
  inside and on our bodies. Most of them are
  completely harmless and some of them are very
  useful. But some bacteria can cause diseases,
  either because they end up in the wrong place in
  the body, or simply because they are 'designed'
  to invade us.

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How are Viruses and Bacteria Spread?

• A person with a cold can spread the infection by
  coughing and/or sneezing.
• Bacteria or viruses can be passed on by touching
  or shaking hands with another person.
• Touching food with dirty hands will also allow
  viruses or bacteria from the intestine to spread.
  

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How are Viruses and Bacteria are Spread.
(continued)

• Body fluids such as blood and saliva can contain
  the infecting organisms and transmission of such
  fluids, for example by injection or sexual
  contact, is important, particularly for viral
  infections like hepatitis or AIDS.

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Shapes of Bacteria

• There are thousands of species of bacteria but
  they all come in 3 different shapes.
• Bacilli are rod-shaped.
• Cocci are spherical.
• Spirilla are spiral-shaped.

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The Virus

• The virus is a type of parasite that is neither
  alive or dead. Inside the head, you see a yellow
  strip. This is the DNA or RNA of the virus.
  Below it is the tail that is connected to the
  end-plate. This is where the legs are
  connected. How Viruses Reproduce

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How A Virus Reproduces

• To reproduce, the virus must inject its RNA into
  the host cell and then mutate that cells DNA to
  match its own. The virus usually dies after this
  encounter but the cell bursts with other viruses
  which then go and attack other host cells.

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How a Bacteria Reproduces

• 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
  can also reproduce sexually.

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Types of Viruses

• Ebola
• Smallpox
• Measles
• Mumps
• Rabies
• Common Cold
• Chicken Pox

• Hepatitis
• HIV
• Influenza
• Polio
• Hanta Virus

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Types of Bacteria (bacilli)

• Streptococcus
• Pneumococcus
• Staphylococcus
• Scarlet Fever
• Rheumatic Fever

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Types of Bacteria (cocci)

• Tuberculosis
• E. Coli
• Tetanus
• Diphtheria

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Types of Bacteria (spirilla)

• Syphilis

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Bacteria Facts

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

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Bacteria Facts (continued)

• Bacteria help our bodies with digestion and
  produce needed vitamins. Bacteria also help us by
  destroying harmful organisms within our bodies.
• Bacteria are used to make cheese, milk, sourdough
  bread and yogurt.
• 99 of all bacteria are helpful.

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Virus Facts

• Viruses are neither classified as dead or alive.
• RNA in Viruses are usually unstable and therefore
  can mutate easily.
• Antibiotics do not work against viruses. You
  either fight them, or die.

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The End