| Viruses are microscopic
organisms. They are not alive, yet they take
control of cells and reproduce, robbing the cells
of nutrients and often destroying them. They
infect human beings with diseases such as
chickenpox, measles, flu,
colds, polio, and AIDS.
Viruses can also infect plants, animals or
bacteria. They are shaped like rods or spheres
and can only be seen with electron microscopes.
Viruses cannot move by themselves and must be
carried to cells by air currents and then by body
fluids to the cells. Some viruses may lay dormant
for years before becoming acitve, as with AIDS. |
FACT: Most
diseases come from other species such as:
Smallpox - dogs
or cattle
Hemorrhagic fevers - rodents and monkeys
Tuberculosis - cattle and birds
Common cold - horses
AIDS - african monkey
|
|
Influenza Virus 
Core of either DNA or RNA in yellow
Coat of protein in blue
|
