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Viruses
Learn
about viruses and their suroundings, and how they are created.
What is a Virus
A virus s a small, NONLIVING particle that invades and then
reproduces inside a living cell.
Viruses
are considered nonliving because they are not cells. They
cannot:
- use
energy to grow
- make
food
- take
in food
- produce
waste
Like
living organisms: they do multiply.
Examples
of Viruses
There
are many viruses in the world. We have all experienced one
at one time or another. If you have ever had the flu or a
cold, that is a virus. Those viruses are relatively minor,
but there are some that are life-threatening.
- small
pox
- cold
sore
- influenza
- cold
- yellow
fever
- ebola
-
anthrax
- AIDS
Viruses
can also cause disease in animals and plants.
Who
is Safe
No living organisms are safe from viruses.
Virus
is a Parasite
A virus is a parasite and cannot survive on its own. It needs
a living host.
How
do viruses multiply
- A
virus attaches to a cell.
- A
viruse enters the cell.
- A
virus takes over the cell's functions.
- The
virus directs the cell to produce the virus's proteins and
genetic materials.
- These
proteins are assembled into new virus particles.
- Soon
there are too many virus particles in the cell and the cell
explodes allowing the viruses to find new cell hosts.
Viruses can be either active or hidden. An active virus immediately
springs into action after entering a cell. The cell starts
immediately producing the virus's proteins and genetic materials.
In a hidden virus, the virus's genetic material becomes part
of the cell.
It's
All in a Name
Because viruses are not alive, they are named after a variety
of things. Viruses are named after the disease they cause
or perhaps the organism they affect or even the place they
were found or the scientist who found it. The Ebola Virus,
for example was named after the location in Africa where it
was found.
Structure
of a Virus
 Viruses
can look very different from one another. They vary in shapes
and sizes. They can be round, rod-shaped, brick shaped, threadlike
or bulletlike, Some can even look like little robots with
a head and a tail and little legs. Viruses are smaller than
cells and cannot be seen with low powered microscopes. Most
range in size from about 50 to 60 nanometers in diameter.
However,
their basic structure is always the same. All viruses have
two basic parts: an outer coat that protects the virus and
an inner core that is made of genetic material. This genetic
material includes the directions for making new viruses.
Spreading
of Human Viruses
If a person coughs on their hand and they are currently sick,
if they wipe it on a handrail at an amusement park, there
is probably going to be a person to comes and touch that spot
with there hand. Then they wipe their nose and the virus might
spread to that person. Later the person who touched the handrail
shakes someone's hand--the virus could then be spread to that
person.
Some
viruses can be spread through the air. Anthrax was a virus
we were all worried about and it could be spread both through
contact and through the air.
Terminating
Viruses
But the virus can be terminated.Scientists are continuously
searching for virus eliminators.
Some
medicine can target the specific virus that is in you body
and wipe it out. Others are still being researched and developed.
Some
preventative measures to avoid viruses can include:
- washing
your hands frequently
- using
anti-bacterial soap and spray
- avoiding
exposure to others who have the virus.
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