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Viruses – Latin for ‘______________’
Viruses are ________ classified as _________________ _______ (they lack ______________, ______________, and ___________________)
Viruses cannot carry any metabolic functions and cannot reproduce on its own.
Viruses must infect a living ________ cells (prokaryotic or eukaryotic in order to reproduce.
Parts of a Virus:
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Viruses contain an inner ______________ ______________ (nucleic acid - DNA or RNA)
Viruses contain a ____________ (an outer protein coat) - provides shape and accounts for 95% of the virus
Scientists classify viruses based on their unique characteristics, including:
 ________ and __________ of the capsid (protein coat surrounding its genetic material)
 ________ and ___________ of the virus
 __________(s) of _________________ the virus causes
 __________of genetic material (__________ or __________)
 method of ____________________
Virus Shape and Structure:
There are different shapes for viruses:
1) ______________ (Spiral)
2) ______________
3) ______________ (many sides with a tail)
Viruses can be ________________________ or ______________________________
Looking In:
Methods of Reproduction:
_____________________________ = the time it takes between when the virus _____________ a cell and when symptoms _______________
(when the virus ruptures the cell).
There are _________ types of reproduction/replication:
 The __________________ Cycle and  The __________________________ Cycle
Lytic Cycle:
 ____________________ & _____________:
- Proteins on the surface of the virus bind to protein receptors on the surface of the host cell’s membrane; The virus injects its genetic material
(DNA or RNA) into the host cell)
___________________:
- The host cell replicates the parts of the virus (synthesis of proteins and nucleic acids).
___________________:
- New viruses are assembled in the host cell.
___________________:
- The host cell bursts open (lysis) and releases the new viruses – they go on to invade other cells
Note: 25-45 min. production of 100s of viruses
Lysogenic Cycle:
 ____________________ & _____________:
- The virus attaches to/invades host cell and injects its genetic material (nucleic acid - DNA or RNA) into the host cell.
_______________________:
- The viral DNA (genetic material) is inserted into the host cell’s DNA and is referred to as a
_________________.
 _______________________:
- The provirus (viral DNA) remains ________________ (inactive) for a period of time while replication of the host cell occurs without any harm to
it.
- A “trigger” or “stimulus” activates the provirus, and it separates from the host DNA. The trigger stimulates the lytic cycle to begin, and the
infection/death of the host cell.
___________________:
- The host cell replicates the parts of the virus (synthesis of proteins and nucleic acids).
___________________:
- New viruses are assembled in the host cell.
___________________:
- The host cell bursts open (lysis) and releases the new viruses – they go on to invade other cells
Humans and Viruses
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Many common human diseases are caused by viruses
Viruses attack cells as it reproduce
The destruction of the cells causes the symptoms of disease
Routes of Transmission: