viruses “they are not alive!”. viruses non-living? viruses do not: metabolize on their own...
TRANSCRIPT
Viruses
“They Are Not Alive!”
Viruses
Non-Living?
Viruses DO NOT: Metabolize on their own Reproduce Move Take in food Grow Consist of cells
What they can do is take a host cell “Hostage”
Bacteriophage
Consist of a protein coat called a Capsid Contain Viral DNA Special Ligands allow the virus to attach
to the cell receptors of a host cell.
Viral Infection
A virus can reproduce in two ways:
1.The Lytic Cycle: infects and affects the host cell very quickly. Flu, Ebola, Cold
2. The Lysogenic Cycle: infects but does not affect immediately HIV, Herpes
The Lytic Cycle
The Lysogenic Cycle
INCUBATION PERIOD
Lytic Cycle Animation
Lytic Cycle #2 Virus Attack H1N1 Lytic Infection PH
Viral Infections Encephalitis Influenza Meningitis Ebola HIV Lassa Fever Mononucleosis Rabies Dengue Fever Yellow Fever H1N1 (Swine Flu)
Small Pox Chicken Pox Herpes Hanta Mumps Measles Polio Hepatitis West Nile Corona
Vaccines
Vaccines are used to establish immunity. They can be made of weakened viruses or
“dead” viruses. The body recognizes and
destroys the viruses. It will“remember” them so that the next time they are in the body, they will be destroyed.
Ex. The H1N1 Shot
More Human Viral Diseases
Chicken Pox Mumps Herpes Hepatitis Warts
How big are Viruses?
Viroids and Prions
Viroids
• Infections agents composed of a single, circular strand of RNA. They are not protected with a protein coat.
• Viroid RNA does not code for any known protein.
• Mostly affect plants but recently have been found to affect humans.
Viroids and Prions
Prions
• An infectious particle made of protein
• Affect the brain or neural tissue.
• All are untreatable and fatal
• Ex. Mad Cow Disease