Lucy+7.1


 * Why are viruses not exactly living or nonliving?
 * - They are not exactly living or nonliving because they are chemicals. The viruses are chemicals that can be stored away and reappear when they are needed. When they reappear and become active they replicate inside cells and become clearly alive.


 * Give some examples of diseases caused by viruses.
 * - There are several diseases caused by viruses such as the flu, chicken pox, polio, rabies, AIDS, colds, Genital warts and genital herpes.


 * What is the basic structure of a virus? (The two parts and their function)
 * - The basic structure of a virus is made up of two parts, an outer capsid they is amde up of protien units and an inner core that contains nucleic acid.


 * Why are viruses like microscopic pirates?
 * - Viruses are like microscopic pirates because they commandeer the metabolic machinery of a host cell.


 * Why are viruses considered parasites?
 * - Viruses are considered parasites because they get into a particular host cell because portions of the virus adhere in a lock- and key manner with a receptor on the host cell's outer surface.


 * Why are viruses considered OBLIGATE parasites?
 * - Viruses are considered obligate parasites because they depend on host cells. They rely on the host's enzymes and ribosomes for its own reproduction.


 * Why do viruses ALWAYS cause disease?
 * - Viruses causes disease because mutations allows a virus to use a new and different insect vector. Viruses always emerge when there is a mutation.


 * How do viruses "emerge" and "spread" each year? Give examples.
 * - Viruses "emerge" and "spread" each year by going to places they have never been before. The flu strains moves from Southeast Asia to the U.S. each year. The West Nile virus is making the headlines because it has changes its range. It is moving to the U.S. and is getting into the bird and mosquito population. Most viruses are spread by vectors, usually by insects that carry infected diseases to healthy insects. Also a disease can emerge when a mutation allows a virus to use a new and different insect vector.


 * What is a virus vector? Give examples,
 * - A virus vector transmits diseases from infected insects to healthy ones, therefore they become infected and it keeps passing one one insect to another.


 * What is the relationship of bird flu to birds?
 * - The bird flu evolved from birds. The birds became ill with this flu and were infected by coming in contact with the saliva, feces, or mucus of another infected bird.


 * How does bird flu infect humans?
 * - The bird flu will infect humans if they become in close contact with birds that are infected with this disease. Humans eat bird everyday, such as chicken, ducks, and geese. Therefore they are in close contact and get infected.


 * What is a pandemic?
 * - A pandemic is the spreading of diseases worldwide.


 * Why is there fear that bird flu could cause a pandemic?
 * - There is fear that the bird flu could cause a pandemic and that the bird flu and the human flu virus would merge. A concern of a new hybrid virus would form. That disease could easily be transmitted from one person to another and become highly infectious. Also two viruses could infect a different host species and swap their genes in that host species. Pigs are a concern because they easily pass it on to human farmers who are in contact with these infected pigs.


 * What action can we take to prevent a bird flu pandemic?
 * - As of right now there is on known vaccination that works against the bird flu. Several drugs are being tested by the results are still iffy.