Name _____________________
Viruses Study Guide
Class Pd. _____
Characteristics of a Virus




__________ membranes, cytoplasm, ribosomes, or other cellular _______________________
they _______________ move or ______________________
they can only ___________________inside a
__________________________cell
______________________- extremely tiny, much smaller than a cell
and only visible with microscopes
Virus Structure



Nucleic Acid—DNA or RNA
_________________________________________
Protein coat called a _______________________________surrounds
nucleic acid core
Outer layer called an ________________________surrounds the
capsid
Parasitic Nature of Viruses



_____________________to
their
____________________________(human, dog, some can cross
species)
They can ______________attack ______________ cells , the common
cold is a virus that specifically attacks cells of the respiratory track
(coughing and sneezing and sniffling). HIV specifically attacks white
blood cells.
_________________________________- a virus that infects bacteria.
Types of Viruses:_________________________________________________________________________________
Viral Reproduction



__________________________________ = reproduction occurs, cells burst
____________________________________ = reproduction does not immediately occur (dormant)
_______________________________________= viruses that undergo _______________________cycles
Lytic Stage

Viruses that use this cycle cause disease_____________________—known as __________________________

Virus invades host cell, produces new viruses, ________________________host cell, and releases newly formed viruses.

__________________________________ = “to burst”
5 Steps of Lytic Stage
1.
Virus____________________________________ to host.
2.
Virus ____________________________________its nucleic acid.
3.
Using enzymes of host, virus _______________________________________________its nucleic acid.
4.
________________________________the new viral _________________________________.
5.
______________________________by bursting/ __________________________ the cell.
Lysogenic Cycle

Viruses that use this cycle infect a cell ___________________ causing immediate _________________________.

Can _____________in host for days, months, or _______________________.

Examples: __________________________________________________
8 Steps of Lysogenic Stage
1.
Virus ________________________to _____________________cell.
2.
________________its nucleic acid.
3.
Virus nucleic acid becomes ____________________into the host cell’s nucleic acid becoming a ___________________.
4.
Host cell replicates with the new virus _______________________.
5.
____________________cell continues to ______________________new virus instruction into each new cell.
6.
Host cell continues to make multiple new cells with the virus inside it.
7.
External stimuli cause the host to enter the lytic cycle
8.
Host cell bursts releasing new viruses and organism starts to feel symptoms of disease
Retroviruses -- _______________viruses that have _____________________stage.
Related to Viruses

____________________________ – even smaller than viruses, consist of RNA strands that lack a protein coat

_____________________- "rogue protein", believed to be the cause of Mad Cow Disease.
How do Vaccines Work?
1. Once you have gotten a virus, such as chicken pox, your ____________________ develops the ________________________to
that virus.
2. _____________________are made by growing a _______________________or killed form of the virus (often grown in
________________________).
3. This form of the virus is ____________________________into a person's body, which causes an
___________________________response, and immunity to the virus.
[Type a quote from the
document or the summary of
an interesting
point.the
You can
[Type
a quote from
position the
box
document
or text
the summary
of
[Type
a quote
from
the
anywhere
in
the
document.
an interesting point. You can
document
or the summary
Use the the
Drawing
Tools tab of
to
position
text box
an
interesting
point. Youofcan
change
the
formatting
the
[Type
a quote
from
the
anywhere
in the
document.
position
theor
text
box
pull
quote
text
box.]
document
the
summary
of
Use the Drawing Tools tab to
anywhere
in
the
document.
change
an
interesting
the formatting
point. You
of can
the
Use
the
Drawing
Tools
tab
to
position
thetext
textbox.]
box
pull
quote
[Type a quote from the document or the summary of
an interesting point. You can position the text box
anywhere in the document. Use the Drawing Tools
tab to change the formatting of the pull quote text
box.]
[Type a quote from the document or the summary of
an interesting
point.the
You
can position
thesummary
text box of
[Type
a quote from
document
or the
anywhere
in
the
document.
Use
the
Drawing
an interesting point. You can position the textTools
box
tab to change
the
formattingUse
of the Drawing
pull quote
text
anywhere
in the
document.
Tools
box.]
tab
to change the formatting of the pull quote text