Virus Video.
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Transcript of Virus Video.
![Page 1: Virus Video.](https://reader035.fdocuments.us/reader035/viewer/2022062217/5697bf951a28abf838c90e57/html5/thumbnails/1.jpg)
![Page 3: Virus Video.](https://reader035.fdocuments.us/reader035/viewer/2022062217/5697bf951a28abf838c90e57/html5/thumbnails/3.jpg)
Viruses & Bacteria can cause infection
• Pathogen - Any disease-causing agent
viruses50-200 nm
prokaryotics cells200-10,000 nm
prion2-10 nm
viroids5-150 nm
eukaryotics cells10,000-100,000 nm
100 nm
1 nanometer (nm) = one billionth of a meter
![Page 4: Virus Video.](https://reader035.fdocuments.us/reader035/viewer/2022062217/5697bf951a28abf838c90e57/html5/thumbnails/4.jpg)
Virus
• 2 basic parts:– protein coat. – Contains DNA or RNA
• non-living pathogen
![Page 5: Virus Video.](https://reader035.fdocuments.us/reader035/viewer/2022062217/5697bf951a28abf838c90e57/html5/thumbnails/5.jpg)
• Viruses have a simple structure.
capsid nucleic acid
lipidenvelope
surfaceproteins
capsid
nucleic acid
lipid envelope
Surface proteins capsidsurfaceproteins
nucleic acid
helical(rabies)
polyhedral(foot-and-mouth
disease)
enveloped(influenza)
![Page 6: Virus Video.](https://reader035.fdocuments.us/reader035/viewer/2022062217/5697bf951a28abf838c90e57/html5/thumbnails/6.jpg)
All viruses have two main parts:
1. DNA or RNA – genetic info
2. Capsid – a protein coat
![Page 7: Virus Video.](https://reader035.fdocuments.us/reader035/viewer/2022062217/5697bf951a28abf838c90e57/html5/thumbnails/7.jpg)
Bacteriophages: viruses that infect bacteria.
capsid
DNA
tail sheath
tail fiber
![Page 8: Virus Video.](https://reader035.fdocuments.us/reader035/viewer/2022062217/5697bf951a28abf838c90e57/html5/thumbnails/8.jpg)
• Viruses enter cells in various ways.
colored SEM; magnifications:large photo 25,000; inset 38,000x
– bacteriophages pierce host cells
![Page 10: Virus Video.](https://reader035.fdocuments.us/reader035/viewer/2022062217/5697bf951a28abf838c90e57/html5/thumbnails/10.jpg)
Viral Replication Picture
http://glencoe.mcgraw-hill.com/sites/9834092339/student_view0/chapter28/life_cycle_of_t2_phage.html
http://www.mcgrawhill.ca/school/schoolGraphics/biology2_1.mpg
![Page 11: Virus Video.](https://reader035.fdocuments.us/reader035/viewer/2022062217/5697bf951a28abf838c90e57/html5/thumbnails/11.jpg)
– Endocytosis (pulled into cell)
• Viruses enter cells in various ways.
![Page 12: Virus Video.](https://reader035.fdocuments.us/reader035/viewer/2022062217/5697bf951a28abf838c90e57/html5/thumbnails/12.jpg)
– fuse with membrane
• Viruses enter cells in various ways.
![Page 13: Virus Video.](https://reader035.fdocuments.us/reader035/viewer/2022062217/5697bf951a28abf838c90e57/html5/thumbnails/13.jpg)
Are viruses alive???Viruses contain DNA/RNA, proteins, and they reproduce…
NO.They contain no nucleus, cytoplasm, organelles or cell membrane; they cannot carry out cell functions, and they can only “reproduce” when an infected cell builds new viruses.
![Page 14: Virus Video.](https://reader035.fdocuments.us/reader035/viewer/2022062217/5697bf951a28abf838c90e57/html5/thumbnails/14.jpg)
Grouping Viruses
• Grouped according to:– Presence of Capsid and envelope – shape– RNA or DNA, single or double stranded – structure
Viral Group Nucleic Acid Shape and Structure Example
Papovaviruses DNA Icosahedral, non-env. Warts, cancer
Adenoviruses DNA Icosahedral, non-env. Resp. & intestinal infections
Herpesviruses DNA Icosahedral, enveloped Herpes simplex, chicken pox, mono, shingles
Poxviruses DNA Complex brick, enveloped Small pox, cow pox
Picornaviruses RNA Icosahedral, non-env. Polio, hepatitis, cancer
Myxoviruses RNA Helical, enveloped Influenza A, B, C
Rhabdoviruses RNA Helical, enveloped Rabies
Retroviruses RNA Icosahedral, enveloped AIDS, cancer
![Page 15: Virus Video.](https://reader035.fdocuments.us/reader035/viewer/2022062217/5697bf951a28abf838c90e57/html5/thumbnails/15.jpg)
Treatment and Prevention
Vaccines – creates antibodies
Anti-viral drugs: interfere with viral DNA/RNA synthesis
Inactivated- the virus is “dead”; cannot replicate
Attenuated- the virus has been genetically altered; still functional,
but won’t cause disease
Attenuated tend to be more effective vaccines
![Page 16: Virus Video.](https://reader035.fdocuments.us/reader035/viewer/2022062217/5697bf951a28abf838c90e57/html5/thumbnails/16.jpg)
Some Pictures are Graphic
![Page 17: Virus Video.](https://reader035.fdocuments.us/reader035/viewer/2022062217/5697bf951a28abf838c90e57/html5/thumbnails/17.jpg)
The Lysogenic CycleWhen viruses remain inactive within host cells for days, months or years.
•Viral DNA inserted directly into the host DNA.•Viral DNA copied with host DNA during replication•Viral DNA passed on to daughter cells during mitosis•Remains dormant (no viral proteins are produced) until some “triggering event”
Examples: Chickenpox and Shingles; HIV
Stress UV light
chemicals
heat
???
![Page 18: Virus Video.](https://reader035.fdocuments.us/reader035/viewer/2022062217/5697bf951a28abf838c90e57/html5/thumbnails/18.jpg)
POXVIRUSESSmall Pox
BACK
![Page 19: Virus Video.](https://reader035.fdocuments.us/reader035/viewer/2022062217/5697bf951a28abf838c90e57/html5/thumbnails/19.jpg)
PICORNAVIRUSES - Polio
BACK
![Page 20: Virus Video.](https://reader035.fdocuments.us/reader035/viewer/2022062217/5697bf951a28abf838c90e57/html5/thumbnails/20.jpg)
Destroys the motor neurons that are
producing the virus. The result is a loss of
muscle control including the diaphragm. The iron lung changes the
pressure to pump air in and out of the lungs.
![Page 21: Virus Video.](https://reader035.fdocuments.us/reader035/viewer/2022062217/5697bf951a28abf838c90e57/html5/thumbnails/21.jpg)
U.S. President
Franklin Delano Roosevelt
![Page 22: Virus Video.](https://reader035.fdocuments.us/reader035/viewer/2022062217/5697bf951a28abf838c90e57/html5/thumbnails/22.jpg)
MYXOVIRUSESFlu Virus
BACK
![Page 23: Virus Video.](https://reader035.fdocuments.us/reader035/viewer/2022062217/5697bf951a28abf838c90e57/html5/thumbnails/23.jpg)
RHABDOVIRUSESRabies
BACK
![Page 24: Virus Video.](https://reader035.fdocuments.us/reader035/viewer/2022062217/5697bf951a28abf838c90e57/html5/thumbnails/24.jpg)
RETROVIRUSES
![Page 25: Virus Video.](https://reader035.fdocuments.us/reader035/viewer/2022062217/5697bf951a28abf838c90e57/html5/thumbnails/25.jpg)
Herpes
![Page 26: Virus Video.](https://reader035.fdocuments.us/reader035/viewer/2022062217/5697bf951a28abf838c90e57/html5/thumbnails/26.jpg)
HPV Tree man
![Page 27: Virus Video.](https://reader035.fdocuments.us/reader035/viewer/2022062217/5697bf951a28abf838c90e57/html5/thumbnails/27.jpg)
![Page 28: Virus Video.](https://reader035.fdocuments.us/reader035/viewer/2022062217/5697bf951a28abf838c90e57/html5/thumbnails/28.jpg)
Ebola
![Page 29: Virus Video.](https://reader035.fdocuments.us/reader035/viewer/2022062217/5697bf951a28abf838c90e57/html5/thumbnails/29.jpg)
Syphilis
![Page 30: Virus Video.](https://reader035.fdocuments.us/reader035/viewer/2022062217/5697bf951a28abf838c90e57/html5/thumbnails/30.jpg)
• Sketch & Label the following:
T4 Bacteriophages
capsid
DNA
tail sheath
tail fiber