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Student Outcome: Students will be able to explain how the hepatitis virus affects the
liver.
Assessment: Concept Quiz
Known Facts:
Virus
 RNA virus,
 has glycoproteins which bind to liver cell membrane receptors.
 Only the liver has receptors that the virus can bind to, other organs not
affected
 Naked virus without spikes
 Viruses enter the cell and change the DNA of the cell and the metabolism
 Need to do this to replicate (viruses do not reproduce)
 Viruses are not living – they are actually chemical parasites
 Viruses attach and are engulfed by the cell membrane
 Virus’ protein coat is removed freeing the viral RNA
 The viral RNA uses the cell’s material to synthesize its own components
(RNA & caposomers (make the coat))
 Components assemble into new viruses
 Viruses are released from the cell to attack other cells
 These processes turn the host cell into a little virus factory whose only
purpose is to make and shed new viruses
 The RNA nucleic acid becomes part of the cell’s DNA – letting it divide
more than it should be
 Eventually the cell dies
Liver
 As the virus reproduces in the liver, several proteins and enzymes,
including many that attach to the surface of the viral protein, are also
produced.
 Some of these may be directly responsible for liver damage. Researchers
are investigating elevated levels of specific immune factors, including T
cell sub-types,
 T cells are important infection fighters in the immune system that can
release powerful inflammatory substances (tumor necrosis factor and
interferon gamma) that may be involved in the damage
 Viruses increase the rate of cell division in liver cells with an increase in
mutations – increase cancer cells?
 Hepatitis B antigens found in malignant cells
 Persistent carriers are more likely to develop the cancer because of the
increase in cell division
 Affected cells accumulate and cause malignancy
 The disease becomes life-threatening only after cirrhosis has developed.
 Cirrhosis - A chronic disease of the liver characterized by the replacement
of normal tissue with fibrous tissue and the loss of functional liver cells.


Viruses cause necrosis of the hepatocytes (liver cells) causing a swelling
and disruption of liver structure that diminishes the production of bile. –
Bilirubin from RBC destruction builds up causing yellow color
Inclusions are cell clumps
Activity I: Viral Replication
Equipment:
Yarn
One color long for cell membrane, and 10 of another color short
for the virus proteins , 10 tiny pieces of a 3rd color for viral RNA
Paper
Cell nucleus,
Steps:
1. Make a cell with the big piece of yarn and the paper nucleus
2. make a virus with the shorter piece for the protein coat
(capsomere which become the capsid) and 1 tiny piece for its
RNA
3. Have the cell membrane engulf the virus (virus can enter where
the yarn piece is open).
4. protein coat opens up inside the cell – caused by cellular
enzymes
5. RNA is free
6. RNA forces cell to make more viral RNA and more capsomids
a. make more viruses with the remaining yarn pieces
7. cell releases new viruses
8. cell swells and bursts and then dies
9. But viruses attack other cells
Activity II. Effect on the liver
Equipment:
Yarn & Paper
Yellow yarn for sick liver cell membranes and paper nuclei–
enough for 10
1 virus from previous activity
crayon
Steps:
1. virus inside liver attaches to liver cell nucleus
2. liver cell skips G2 phase of the cell cycle (forgets how to rest between
divisions)
3. cell multiplies uncontrollably – make 9 new cells
a. this increases the possibility of mutation
b. Color in different DNA in 1/4 of the new cells.
4. some of the new cells are possibly cancer cells and no longer carry on
the functions of the liver
5. rapid cell division also disrupts the production of bile – causing the
yellow color
Hepatitis Virus Concept Quiz
Name __________________
1. Bobby is infected with the hepatitis virus. Describe the method the virus used to
make more of itself. Include parts of the virus, how they are made, and how the
virus entered its host cell. 5 points
2. Explain two effects the hepatitis virus can have on a cell. Include how the virus
brought about these affects. 5 points
Bonus Question: When Bobby was infected how did the virus how does it recognize
its host cell?