Did You Know?
Viruses have been around so long
that dinosaurs battled them.Mosquitoes, fleas,
and ticks serve as carriers for some diseases. These
and other arthropods pick up a disease when they bite
a sick or infected host, and then carry it to one or
more new hosts during their next meal of blood. Today
we know that mosquitoes were already feeding on blood
millions of years ago. How do we know? Many insects
were caught in sticky tree sap, which hardened into
amber. Scientists have been able to study these preserved
specimens.
Even germs can get and die from
germs.Bacteriophage, which means bacteria-eater
in Greek, is a virus that looks like a landing pod.
With its six legs, the bacteriophage, or phage for short,
attaches to the surface of much larger bacteria. Most
use their tails to inject viral DNA into the host cell,
where it directs the production of offspring phages,
sometimes creating more than a hundred in half an hour.
An infected bacterium creates so many copies of the
phage that the cell bursts.
Viruses once made tulips valuable
commodities.The stripes and bright color streaks
found in tulips are caused by viruses. Today these infected
tulips are commonplace. But that was not the case hundreds
of years ago. In Holland in the 1600s, the flowers were
highly prized. People traded bulbs like jewels. Farmers
offered their daughters? hands in marriage and
even sold their farms for the thrill of owning one infected
bulb.
Scientists hope that viruses will
help cure diseases.Viruses are experts at injecting
genetic information into a cell and harnessing that
cell to create new viruses. That?s why scientists
are working on ways to manipulate exactly the kind of
information a virus can inject into a cell. Having viruses
inject other kids of information, in the form of DNA,
into cells is called gene therapy. Scientists hope that
gene therapy will be able to stop cancer and AIDS, and
cure genetic disorders such as cystic fibrosis. |
