1. VIRUSES!

2. Introduction – Structure – Replication – Virology – Medicine – Review
WHAT IS A VIRUS?
Introduction – Structure – Replication – Virology – Medicine – Review

3. VIRUS
It is NOT ALIVE …depends on a host cell to reproduce.

4. Introduction – Structure – Replication – Virology – Medicine - Review
A VIRUS is either DNA or RNA, that is protected by a protein coat called a CAPSID.
CAPSID
(protein Coat)
DNA
VIRUS
Introduction – Structure – Replication – Virology – Medicine - Review

5. Why are some viruses harmful?
Virus invades cell
When your cells make viruses instead of operating normally, YOU get sick
Virus forces cell to make copies of virus
Eventually so many copies are made, the cell explodes,
releasing all of the new viruses
Introduction – Structure – Replication – Virology – Medicine - Review

6. Examples of some viral diseases:
VIRUSES
AIDS
HIV
Wart
Herpes Simplex
Virus
Flu
Influenza
Measles
Morbillivirus .
Cancer
Hepatitis B
Introduction – Structure – Replication – Virology – Medicine - Review

7. Introduction – Structure – Replication – Virology – Medicine - Review
Who do viruses infect?
Viruses usually infect a specific host including:
Viruses infect Bacteria
These viruses are called bacteriophages
Viruses infect Plants
One example is the Tobacco Mosaic Virus
Viruses infect Animals
One example is the common cold
Introduction – Structure – Replication – Virology – Medicine - Review

8. Adenovirus
Adenoviruses cause diseases like pink-eye or the common cold
Introduction – Structure – Replication – Virology – Medicine - Review

9. Bacteriophage Bacteriophage is a virus that infects bacteria.
Introduction – Structure – Replication – Virology – Medicine - Review

10. How do viruses replicate?
Introduction – Structure – Replication – Virology – Medicine - Review

11. Introduction – Structure – Replication – Virology – Medicine - Review
Replication Phases
I, II, III - Viruses enter cell
Attachment to cell membrane
Penetration inside cell
Losing virus protein coat
Phase I
IV - Replication
Tricks cell into making more viral DNA
Tricks cell into making viral protein coat
V - Release
Assembly of virus DNA and protein coat into whole new viruses
Leaving the cell
Phase II
Phase III
Phase V
Phase IV
Introduction – Structure – Replication – Virology – Medicine - Review

12. - Viruses
How Viruses Multiply
Active viruses enter cells and immediately begin to multiply, leading to the quick death of the invaded cells.

13. - Viruses
How Viruses Multiply
Hidden viruses “hide” for a while inside host cells before becoming active.

14. Introduction – Structure – Replication – Virology – Medicine - Review
The End
Introduction – Structure – Replication – Virology – Medicine - Review

15. Click the Video button to watch a movie about deadly viruses.