Notes on Viruses What are viruses?● A virus is a __________________particle

made up of genetic material and protein that can invade living cells and reproduce.

● They are ________________(NOT alive).

What are the characteristics of viruses?● With the ability to_________________,

viruses __________ nearly every characteristic of life

● Not composed of cells● Do not respond to stimuli● Do not use energy for growth and development● Need electron microscope to see

How are viruses structured?● ________or

________(retrovirus) surrounded by protective protein coat (capsid)

● Genetic material carries information for _______________

How are diseases caused by viruses?● Cause disease by either

______________or ____________ cells● First ________________itself to a

healthy _____________and then injects its DNA or RNA into cell

● Hijacks (takes over) biochemical machinery of host cell

● Then replicates once __________infected cell

How viruses can be spread● Don’t forget… we already listed in our “Introduction to

Infectious Diseases and Bacteria” notes how disease is spread. Here is a reminder….

● Infectious disease can be spread through:○ Water○ Food ○ ________○ _____________- with object, person, animal○ Body fluids○ Vectors

How do we prevent viruses?● No Cure, just prevention with_______________.● What are vaccines?

○ Vaccines: a substance introduced into the body to stimulate the production of chemicals that destroy specific viruses

● Cannot use antibiotics. Antibiotics are used to treat bacteria

● Vaccinations ________________viruses.● Some anti-viral drugs are used to inhibit the development

of viruses (does not destroy them)

Viruses● Viral diseases are among the most

__________________illnesses in humans. ● These illnesses range from mild __________to

some forms of cancer and include several other severe and __________diseases.

Diseases caused by virusesExamples:

● Influenza (the_________)● Common ___________● Polio● Rabies● West Nile Virus● ______________● Measles