1. Viruses (18.2) SB3D. Compare & contrast viruses with living organisms.
State Standard
SB3D. Compare & contrast viruses with living organisms.

2. Why aren’t they considered to be living?
Viruses—An Exception
A virus is a nucleic acid (__________) surrounded by a protein coat (__________).
Why aren’t they considered to be living?
Viruses are _______________, nor are they made of cells.
Viruses __________________ without a __________ cell.
Viruses __________ the machinery needed to carry out the functions of life.
Because viruses are __________, they usually are not placed in the biological classification system.

3. More virus traits…
the core can be made of _____ or _____ (but never both!)
very __________
NOT __________
Can reproduce by __________ living cells.
The capsid helps the virus __________ to the host cell.

4. E. Coli and the Bacteriophage
What it looks like in real life

5. There are two types of viral infection cycles:
__________ (Active)
__________ (Dormant)

6. Lytic (active) Infection
Virus __________ the host cell.
Virus makes __________ of itself.
The new copies cause the cell to __________.

7. The
Lytic
Cycle

8. Lysogenic (dormant) Infection
A virus __________ its DNA into the DNA of the host cell.
The virus’s __________ is __________ (copied) along with the host cell’s DNA.
The cell does NOT __________ immediately.
Certain conditions can cause the __________ virus to __________ to an active lytic cycle.

9.                                                                 
The
Lysogenic
Cycle

10. Viruses often cause observable __________
Antibiotics are __________ against viruses, because viruses are not __________
Ex. AIDS, Smallpox, Polio, Measles, the Common Cold

11. Vaccines
Since viruses can’t be cured, our only defense against them is __________
We accomplish this through the use of __________
Vaccines contain a __________ or __________ form of the virus that is __________ into the body.

12. Retrovirus Changes DNA into __________ Mutates quickly
And example of a Retrovirus is __________