Viruses

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Viruses
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When is a life form not a life form?

• When its a virus!
• Viruses are strange things that straddle the
  fence between living and non-living. On the one
  hand, if they're floating around in the air or
  sitting on a doorknob, they're inert. They're
  about as alive as a rock. But if they come into
  contact with a suitable plant, animal or
  bacterial cell, they spring into action. They
  infect and take over the cell like pirates
  hijacking a ship.

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• A virus is basically a tiny bundle of genetic
  materialeither DNA or RNAcarried in a shell
  called the viral coat (or capsid)

Flu virus
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What kind of Microbe is it?

• Microbes are single-celled organisms that can
  perform the basic functions of life metabolism,
  reproduction, and adaptation.

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• Except viruses. Viruses cant metabolize
  nutrients, produce and excrete wastes, move
  around on their own, or even reproduce unless
  they are inside another organisms cells.

HIV Virus
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They arent even cells.

• Diagram of Flu virus

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• When viruses come into contact with host cells,
  they trigger the cells to engulf them, or fuse
  themselves to the cell membrane so they can
  release their DNA into the cell.

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• Once inside a host cell, viruses take over its
  machinery to reproduce. Viruses override the host
  cells normal functioning with their own set of
  instructions that shut down production of host
  proteins and direct the cell to produce viral
  proteins to make new virus particles.

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• Some viruses insert their genetic material into
  the host cells DNA, where they begin directing
  the copying of their genes or simply lie dormant
  for years or a lifetime. Either way, the host
  cell does all the actual work the viruses simply
  provide the instructions.

Hiv virus
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• Viruses may be able to infect and reproduce in
  more than one kind of animal, but the same virus
  can cause different reactions in different hosts.
  
• For example, flu viruses infect birds, pigs, and
  humans. While some types of flu viruses dont
  harm birds, they can overwhelm and kill humans.
• Plant viruses do not infect animals or vice
  versa. Viruses that infect bacteria do nothing to
  animal or plant cells.

Swine flu virus
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• Viruses exist for one purpose only to reproduce.
  To do that, they have to take over the
  reproductive machinery of suitable host cells.

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Virus or Bacteria?

• Because bacteria and viruses cause many of the
  diseases we're familiar with, people often
  confuse these two microbes. But viruses are as
  different from bacteria as goldfish are from
  giraffes.

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• For one thing, they differ greatly in size. The
  biggest viruses are only as large as the tiniest
  bacteria.

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• Another difference is their structure. Bacteria
  are complex compared to viruses.

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• A virus may or may not have an outermost spiky
  layer called the envelope. All viruses have a
  protein coat and a core of genetic material,
  either DNA or RNA. And that's it. Period.

HIV Virus
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• Viruses are moochers. They contain only a limited
  genetic blueprint and they don't have the
  necessary building tools. They have to invade
  other cells and hijack their cellular machinery
  to reproduce. Viruses invade by attaching to a
  cell and injecting their genes or by being
  swallowed up by the cell.

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• These are T4 bacteriophages (back-tear-e-oh-faj-es
  ). They are a kind of virus that infects
  bacteria. Here they are landing on the surface of
  an E. coli bacterium.

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• The bacteriophage cuts a hole in the E. coli's
  cell wall. It then injects its genetic material
  into the bacterium. By taking over the E. coli's
  genetic machinery, the viral genes tell the
  bacterium to begin making new virus parts. These
  parts come together to make whole new viruses
  inside the bacterium.
• Eventually so many new viruses are made that the
  E. coli bursts open and dies, releasing all those
  new viruses to infect more cells

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The way that viruses spread is specific to the
type of virus. They can be spread through the
following means

• Carrier organisms - mosquitoes, fleas
• The air
• Direct transfer of body fluids from one person to
  another - saliva, sweat, nasal mucus, blood,
  semen, vaginal secretions
• Surfaces on which body fluids have dried
• Virus Video http//www.npr.org/templates/story/sto
  ry.php?storyId114075029

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Are viruses and bacteria treatable?

• Well most bacteria are easily treatable with
  an antibiotic which is prescribed by the doctor.
• Howeversince viruses take over cells in your
  body, they are not easily treated. Usually it is
  left up to your immune system to deal with the
  virus. There are some new antiviral drugs
  becoming available but only for a few viruses.
• The best thing is to avoid getting a virus in the
  first place.

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To reduce the risk of spreading or contacting
viruses, here are things you can do

• Cover your mouth or nose when you sneeze or
  cough.
• Wash your hands frequently, especially after
  going to the bathroom or preparing food.
• Avoid contact with the bodily fluids of others.
• These practices are not foolproof, but they can
  help you reduce the risk of viral infection.

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Sources

• http//www.netdoctor.co.uk/health_advice/facts/vir
  usbacteria.htm
• http//www.microbeworld.org/
• http//www.nationalgeographic.com/
• https//eapbiofield.wikispaces.com/ErikaPR9Clas
  sification?fprint