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Microbiology Unit Cover Page
(see guidelines on page 27)
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Microbiology Unit Front Page
At the end of this unit I will be able to:
 Explain differences between bacteria and viruses
 Distinguish between a lytic and lysogenic infection
 Demonstrate proper lab technique for streaking plates and culturing
bacteria.
 Compare/contrast how bacteria reproduce asexually and sexually
 Describe exponential growth and predict the effects of antibiotics on bacteria
populations.
Roots, prefixes, and suffixes I will understand are:
 Bacteria: pro-, karyon, bact, bacteri, -septic, micro-, anti-, a-, pro-, karyo, peptido-, karyo, glycan, archae-, septic
 Viruses: gen, retro-, phage, sub-, glyco-, cap, -sid, lyso-, -gen, nano-, -mere
The terms I will be able to clearly define are:
 Bacteria: Antibiotic, archaebacteria, aseptic, bacilli, binary fission, cocci, conjugation, gram
negative, gram positive, micrometer, peptidoglycan, plasmid, prokaryotic, spirilla, spore,
vibrios
 Viruses: Acellular, bacteriophage, capsid, dormant, enzyme, lysogenic infection, lytic
infection, nanometer, parasitic, retrovirus
The assignments I will have completed by the end of this unit are:
 Microbiology Cover Page (Page 191)
 Prokaryotic Cell vs. Virus (Page 193)
 Bacteria Notes (Pages 194-197)
 Microbiology Lab Basics (Pages 200-201)
 Exponential Growth Song Lyrics (Page 203)
 Antiseptic Comparison Lab (Pages 204-210)
 “The Doctor’s World” (Pages211-217)
 Socratic Seminar (Pages 211-220)
 Virus Notes (Pages 224-227)
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Prokaryotic Cell vs. Virus



Sketch and label the prokaryotic (bacterial) cell, Figure 18.3 on page 518 of your textbook.
Sketch and label the typical bacteriophage, Figure 18.11 on page 527 of your textbook.
Sketch an example of either the adenovirus or the influenza virus, Figure 18.11 on page 526.
For this assignment you must:
 Be neat
 Use 4 or more colors
 Horizontally label all of the structures
Prokaryotic Cell (Bacteria)
Bacteriophage
(virus that attacks bacteria)
Adenovirus or Influenza Virus
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Bacteria Notes
Draw an example of each bacterial shape below:
194 | P a g e
Rod-shaped (Bacilli)
Comma-shaped
(Vibrios)
Spherical (Cocci)
Spiral (Spirilla)
Bacteria Notes
______________________: Prokaryotic Organisms
– Pro: Primitive or “________________________________”
– Karyon: _______________________ or kernel
– ___________________-celled organisms _____________ a nucleus
– Has circular _________________.
– Often has “________________________” DNA that helps codes
for genes to increase fitness (ex. _____________ ____________)
– Bacteria can be measured in _______________________________
• 0.000001m or 10-6
What is the basic
definition of bacteria?
What are the two main
groups of bacteria and
how are they different?
Two main “domains” or groups:
1. _______________________________
Cell walls with peptidoglycan
1. Made up of types of __________________ and _________________ bonds
2. ______________________________
2. Cell walls __________________ peptidoglycan
3. Adapted to _____________________ environments:
 Extremely hot and cold, salty, without oxygen, etc.

What are the basic
shapes of bacteria?




What is the difference
between gram-positive
and gram-negative
bacteria?

Rod-shaped (_______________________)
Bacillus anthracis (Anthrax),
Yersinia pestis (Bubonic plague)
Comma-shaped (__________________________)
Vibrio cholerae
Spherical (__________________)
Streptococcus, Staphylococcus
Spiral (___________________________)
Treponema pallidum (Syphillis)
Gram-_________________: Retains the crystals of __________________
dye in the peptidoglycan of the cell wall.
• Only has an ______________ layer of plasma membrane
• Infections treated by antibiotics such as penicillin, which
attacks the __________________ of the cell wall.
Gram-_________________________: Will not pick up much the violet
dye because the cell wall is covered by an additional
_______________ membrane, and instead appears _________________.
• Infection treated by a broad-spectrum antibiotic such as
ciprofloxacin that enters the bacteria and disrupts
________________ _________________.
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Binary Fission & Conjugation
In the space to the right,
show the binary fission of a
bacterium. Use one color to
represent the bacterium’s
DNA.
(+)
(-)
In the space to the left, show
the conjugation of two
bacteria. Use one color for the
(+) bacterium’s DNA, another
color for the (-) bacterium’s
DNA, and another color for the
plasmid.
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Bacteria Notes
•
Plasmids are circles of DNA that can _______________________________
separately from a bacterial DNA.
•
Plasmids may carry genes that allow bacteria to survive
exposure to ____________________________________.
•
_________________________:
• ______________________ division
• DNA replicates and cytoplasm divides
• Creates two genetically ____________________ cells from _____
parent cell
_________________________:
• Not true sexual reproduction
• Sex pilus extends between bacteria
• _______________________________ is transferred from one
bacterium to another to introduce __________________
_______________________
_______________ formation:
• Occurs when growth conditions are ____________________
• An endospore is a “spore” with a thick internal wall of
membrane that encloses and _________________ its
________________
What are plasmids?
•
What are the ways that
bacteria can reproduce?
•
Explain the difference between
microbes, microorganisms,
and pathogens using the
Venn diagram to the left.
P a g e | 197
Exponential Growth of Bacteria Activity
One single bacteria lands on a kitchen counter. It divides into two parts every 20 minutes. Fill out
the first two columns in the chart below to show how many bacteria are on the counter after 5
hours. Some parts of the chart have already been filled out as an example. After the table has been
filled out, complete a LINE GRAPH of your data on the next page. Make sure to label the x and y axis
and give your graph a title.
minutes (x)
# of bacteria (y)
Express in Exponents
0
1
1 = 11
20
2
2 = 21
40
4
4 = 2 X 2 = 22
60 (1 hour)
8
8 = 2 X 2 X 2 = 23
80
100
120 (2 hours)
140
160
180 (3 hours)
200
220
240 (4 hours)
260
280
300 (5 hours)
Think about how you filled out your table. 4 bacteria can be written in exponents as 2 x 2 or 22.
8 bacteria can be written as 2 x 2 x 2 or 23. Now complete the last column in the table and fill in
the information below.
1. Express the number of bacteria after 80 minute periods using exponents. __________
2. Express the number of bacteria after 120 minute periods using exponents. __________
3. Express the number of bacteria after 240 minute periods using exponents. __________
4. Express the number of bacteria after 300 minute periods using exponents. __________
5. Bacteria is said to reproduce “exponentially.” What might this mean?
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Exponential Growth of Bacteria Activity
Title of Graph:
6.
Is the graph steady? If so, from when to when?
7.
From what point(s) in time do you notice the graph increasing slightly?
8. From what point(s) in time do you notice the graph begin to increase sharply?
9. Based on this information, when is the rate of bacterial growth fastest?
10. At 225 minutes, how many bacteria were on the kitchen counter?
11. At 250 minutes, how many bacteria were on the kitchen counter?
12. Explain what process you used to figure out your answers to questions 8 and 9.
13. If you had 15,000 bacteria on the kitchen counter, for how many minutes were the bacteria
dividing on the counter?
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Microbiology Lab Basics
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Microbiology Lab Basics
Agar plate streaking
technique
Inoculating loop
After incubation…
After incubation…
Bacterial lawn:
Solid growth of
bacteria without
distinct colonies.
Colonies:
Individual
clusters of
bacteria.
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Microbiology Lab Basics
Aseptic Technique:









Before beginning, wash your hands with soap and water and clean your work surface with a
10% bleach solution.
Never leave a culture dish open, even for a short time when viewing colonies of organisms.
When it is necessary to open a dish, keep the lid close to the dish, open it only as far and as
long as is necessary to accomplish the procedure. Do not contaminate the lip of the petri
dish by setting it down on a non-sterile surface or by touching it with your hands.
If it is necessary to set the lid of the petri dish down, invert the lid and place it upside down
on a sterile surface.
For most bacterial cultures you will use a sterile loop or needle to inoculate. Once an
instrument is sterile, be careful not to touch it to any non-sterile surface.
Flame a loop or needle to red-hot just prior to use, burning off any organic material. Allow
the instrument to cool before to touching a culture or else you will kill it. Do not cool the
instrument by waving it in the air.
Re-sterilize the instrument after performing the procedure. Afterwards, put it down safely
without burning the bench, you, or another student.
Always be aware of where your hands are, where your face is, and whether or not your
culture is in a position to be contaminated.
If you have long hair, make sure it does not hang into your plate. Hair is full of potential
contaminants, and is one of the principle sources of contaminating microorganisms
Warm Up:
Lance visits a doctor and learns he has a bacterial infection for which the doctor prescribes an
antibiotic. Lance asks the doctor what the bacteria look like, and the doctor shows him a
photograph of the bacteria. Which does Lance observe in the photo?
A.
B.
C.
D.
A small nucleus with a thin membrane.
Complex organelles such as mitochondria.
Fragments of RNA but no DNA strands.
Long, whip-like structures called flagella.
Explain.
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Exponential Growth Song Lyrics
When I’m in a place that’s moist and warm,
And I’m so lonely I could cry,
Through cellular division,
I start to multiply.
Give them conditions that are favorable,
Every twenty minutes we will self-divide,
1, 2, 4, 8,
16, 32, 64, 128, 256,
Ok, I said five hundred and twelve,
I said one thousand and twenty four,
I said two thousand and forty eight,
I said four thousand and ninety six,
Eight thousand one hundred and ninety two,
Sixteen thousand three hundred and eighty four
We’re going to multiply through your body,
We’ll multiply exponentially,
We’ll colonize your intestine,
We’ll make you sick,
We’ll make you nauseous,
We’ll give you diarrhea,
We’ll multiply, multiply, multiply, multiplyyyyy!
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Antiseptic Comparison Lab – Flow Chart
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Antiseptic Comparison Lab – Data
Quadrant
A
Antiseptic applied
Sterile distilled water
B
Garlic
Size of Halo (in mm)
C
D
A
B
A
Halo Size
B
C
D
Station 1
Station 2
Station 3
Station 4
Station 5
Station 6
Station 7
C
D
Station 8
Average
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Antiseptic Comparison Lab – Abstract & Procedure
Abstract:
Purpose:
To compare the effectiveness of different antiseptics.
Problem:
In your own words, restate the purpose in the form of a question.
Hypothesis:
If the antiseptic effects of ___________________________________________, ________________________________________,
and ___________________________________________ are compared, then ___________________________________________
will be most effective in preventing bacterial growth because
Materials:
Petri dish with agar, inoculating loop, gas flame, 10% bleach solution, wax pencil/marker, sterile
distilled water, various antiseptics, and forceps
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Antiseptic Comparison Lab – Procedure
Sterilizing:
1. Sterilize your work surface with a 10% bleach solution.
2. Carefully draw on the underside of the petri dish with a wax pencil or marker, dividing it into
quadrants. Label the quadrants A, B, C, & D.
Inoculating:
3. Sterilize your inoculating loop by placing it in a gas flame until it turns red. Allow it to cool for
approximately one minute (do not blow on it!).
4. Touch the loop to a colony in the stock bacteria plate.
5. Quickly and carefully open the petri dish slightly and spread the loop over one of the four
quadrants. (see image below)
6. Sterilize the loop again by placing it in the gas flame.
7. Repeat steps 3-6 for the remaining quadrants of the petri dish.
Adding Antiseptics:
8. Heat sterilize the forceps by placing them in a gas flame until the tip turns red. Allow to cool for
approximately one minute.
9. Pick up a piece of punched filter paper with the sterile forceps.
10. Using a dropper, drop distilled water onto the filter paper until both the front and back of the
paper is saturated with antiseptic. The paper should be saturated, but not dripping.
11. Carefully place the saturated filter paper onto quadrant “A” of the petri dish. Be sure not to
touch any of the other quadrants.
12. Sterilize the forceps again by placing them in the gas flame.
13. Repeat steps 8-12 for the remaining quadrants of the petri dish, using antiseptics rather than
distilled water. Refer to the data sheet on page 205 and be sure to record the specific antiseptics
you use.
Incubating:
14. Tape around the edges of the petri dish. Label the dish with one group member’s name and the
period.
15. Place the dish upside down in the incubator for 24-48 hours.
16. After 24-48 hours, remove your petri dish and draw your observations on your data sheet (page
205.) Measure the “halo” where bacteria did not grow around each piece of paper (if possible).
Record on your data sheet.
lawn of bacteria
A
C
halo (no bacteria)
paper
B
Inoculation:
Be sure to sterilize
between each
section!
A
Measuring the Halo:
Measure from the edge
of the paper to the
outside of the halo.
D
P a g e | 207
Antiseptic Comparison Lab – Conclusion
Organize your conclusion into paragraphs. Be clear and remember to use topic sentences as well as
transitional sentences between paragraphs. Each paragraph should meet all of the points below and
contain at least 5-7 sentences.
Paragraph #1 (RE): Restate the problem and what you thought would happen. Explain which
antiseptics were used. Confirm or reject your hypothesis based on the data. Describe the overall
class results and determine which antiseptic was most and least effective at preventing bacterial
growth. Tell how you are evaluating the “effectiveness” of the antiseptic and why we used sterile
distilled water as a control.
Paragraph #2 (PE): Describe any errors that occurred during experimentation. If there were no
errors, describe any potential errors that could have occurred that can change the results. Are there
any inherent errors that cannot be controlled? Why was it important to follow aseptic techniques?
Paragraph #3 (PA): Make suggestions for further improvement of this investigation. If you had to
change the procedure of this experiment, how would you change the experiment to make it better?
What other experiments can we set up to better understand and investigate bacteria? Describe any
“real world” applications of this lab.
Before you begin writing, outline your conclusion in the space below:
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Antiseptic Comparison Lab – Conclusion
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Antiseptic Comparison Lab – Conclusion
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Tracking the Spread of Antibiotic Resistance
You wouldn’t expect a cat to exchange DNA with a dog, or a giraffe to reproduce with a mouse. But
among bacteria, it’s not uncommon for different species to swap pieces of DNA. In fact, it’s one of the
ways in which bacteria increase their genetic diversity. In a process called conjugation, one bacterium
extends a tube to another bacterium and delivers a segment of DNA to it. Conjugation is one way in
which bacteria can acquire new genes—including genes we don’t want them to have, such as ones that
give them the ability to resist antibiotics. In this activity, you will model how conjugation helps genes for
antibiotic resistance spread through a population of bacteria.
Round 1
1. Get a paper bag—representing a bacterial cell— from your teacher. In it are colored paper discs that
represent plasmids, rings of DNA found in most bacteria species. Plasmids often contain genes for
antibiotic resistance. Don’t reveal what’s in your bag.
2. Circulate around the room. Without looking, take one circle out of another student’s bag and place
it inside your bag. The student from whom you took a circle should take one from your bag. Repeat
until you have made a total of five exchanges with different students. Count the yellow circles in
your bag, and complete the table Tracking the Spread of Antibiotic Resistance chart as a class.
3. Predict what the outcome will be if you repeat Round 1. Write your predictions in the chart on the
next page.
Round 2
1. Repeat Steps 2 and 3 from Round 1.
2. Predict what the outcome will be if you repeat Round 1, only this time, you also will expose the
population to an antibiotic. (NOTE: Yellow circles represent plasmids carrying a gene for antibiotic
resistance.)
Round 3
1. Simulate antibiotic exposure by sitting out this round if you have no yellow circles.
2. For those remaining, repeat Steps 2 and 3 from Round 1.
3. Count the yellow circles in your bag and complete the chart as a group.
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Tracking the Spread of Antibiotic Resistance
212 | P a g e
Tracking the Spread of Antibiotic Resistance
Conclusion Questions:
1. In the activity, what does the following represent:
A. yellow circles
B. the bag
C. your arm and hand
2. What is the trend of antibiotic resistance as seen in this simulation?
3. Explain why some students had to sit out Round 3.
4. How do you predict ‘bacteria’ with different numbers of yellow circles might react to
repeated exposure to an antibiotic?
5. If you have an infection and your doctor prescribes an antibiotic, why is it important to
complete the full ten-to-fourteen day course of the medication, rather than to stop as soon
as you start feeling better?
P a g e | 213
THE DOCTOR'S WORLD:
Encephalitis Outbreak Teaches an Old Lesson
By LAWRENCE K. ALTMAN, M.D
Published: September 28, 1999
When you hear hoof beats, don't think of zebras.
To doctors, the axiom is a call to focus on common ailments and not waste time on
the exotic. But on those rare occasions when they do detect a zebra, doctors say they need to
take extra steps in their investigation to make sure they have identified the right one.
A case in point is the encephalitis outbreak that is blamed for at least three deaths in
New York City. Earlier this month, the Centers for Disease Control and Prevention in
Atlanta and the New York City Health Department said the cause was the mosquito-borne St.
Louis virus, which had never been identified in New York City before.
But last weekend the C.D.C., responding to findings from laboratory tests performed
by Dr. Tracey McNamara, a pathologist at the Bronx Zoo, announced that the outbreak was
caused by an even rarer zebra: the West Nile virus from Africa. Dr. W. Ian Lipkin, of the
Emerging Diseases Laboratory at the University of California at Irvine, confirmed the
findings
The viruses are closely related, causing virtually the same type of inflammation of the
brain. But the West Nile virus had never before been detected in the Western Hemisphere.
''C.D.C. would not have made the diagnosis of West Nile virus as quickly without Dr.
McNamara's persistent medical sleuthing,'' Dr. Duane J. Gubler, the head of the C.D.C.'s
arbovirus field station in Fort Collins, Colo., said in an interview.
The change in diagnosis, though not important in terms of the spraying and other
public health measures taken to combat the outbreak, was scientifically embarrassing to the
C.D.C., the premier Federal agency that is responsible for tracking infectious diseases in this
country.
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THE DOCTOR'S WORLD:
Encephalitis Outbreak Teaches an Old Lesson
In recent years, C.D.C. and other health officials have led a campaign against the
threat of new and emerging infections, warning doctors to expect more infectious disease
''zebras,'' like the sudden appearance of old microbes in new areas.
In fact, health officials thought they had scored a coup when they diagnosed the
mysterious illness as the St. Louis virus. The disease is usually found in the Southeastern
states, and humans are usually bystanders in such infections. Birds are the principal reservoir
for the arboviruses, but they do not become sick. Instead, mosquitoes transmit the viruses to
people, who may become ill.
In hindsight, the concurrent deaths of an unusual number of birds in the city has
turned out to be an important but underestimated clue. Federal and local medical sleuths did
not immediately relate the bird die-off to the human outbreak because West Nile, St. Louis
and similar encephalitis viruses generally do not kill birds.
Now the C.D.C. is retesting blood and spinal fluid from patients who had symptoms
of encephalitis and who did not show evidence of the St. Louis virus.The new findings mean
that health workers need to investigate a number of other possibilities, Dr. Gubler said.
A critical one is that the C.D.C. can no longer be certain that the West Nile virus has
never been present in the United States, because the Federal scientists never specifically
checked for it in earlier outbreaks and individual cases. In testing mosquitoes and specimens
from humans with encephalitis, the C.D.C. routinely checks all types of viral encephalitis
known to have caused infection in the Western Hemisphere, Dr. Gubler said.
There can be considerable overlap in findings from the laboratory tests unless extra
steps are taken to distinguish between the many types of encephalitis-causing arboviruses. In
a sense they are all one virus, but with many variations that can be detected in the laboratory.
The encephalitis they cause is the same disease, although there can be subtle differences in
the type of brain damage they produce.
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THE DOCTOR'S WORLD:
Encephalitis Outbreak Teaches an Old Lesson
The viruses occur in different geographic areas, and by scientific custom they are
named for the area where they were discovered. They include Murray Valley encephalitis in
Australia, Japanese encephalitis, and Rocio virus in Brazil and Argentina. They are
distinguished in the laboratory by small differences in the proteins in the covering of the
virus known as its envelope.
''We don't include West Nile, Japanese and other encephalitis viruses because they
have never been known to be here,'' Dr. Gubler said, adding that in the New York outbreak,
''we had tunnel vision on St. Louis virus, because all the clinical, epidemiological, laboratory
and geographic features pointed to St. Louis.''
''We've learned a lesson here,'' Dr. Gubler continued. ''We've got to be more openminded.
''Once we get past this crisis, we are going to have to go back and check specimens
from C.D.C. and state health departments to see if it has been here, and if so for how long.''
The West Nile virus was discovered in 1937 in Uganda. Since then ''it has rarely
reared its head,'' Dr. Gubler said, though outbreaks and occasional cases have been reported
from Israel, France, Romania and elsewhere in Europe. Presumably the virus was carried
northward by birds migrating from Africa.
After a nearly two-decade silence, West Nile virus caused a large outbreak in
Romania in 1996. This year, West Nile virus apparently caused illness among humans in
Volgograd, Russia, though Dr. Gubler said he had received no reply to an inquiry he has
made to Russian scientists about the outbreak. Lack of communication among scientists
thwarts efforts to learn why a virus is spreading.
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THE DOCTOR'S WORLD:
Encephalitis Outbreak Teaches an Old Lesson
When birds began dying in and near the Bronx Zoo, Dr. McNamara, the pathologist
there, initially thought the deaths might be a result of viruses that cause avian influenza,
Newcastle disease, fowl cholera or Eastern equine encephalitis, Dr. Gubler said.
Dr. McNamara sent the specimens to the Department of Agriculture Laboratory at
Ames, Iowa, where scientists eliminated those candidates. Because the Ames laboratory
lacked the material to test for the pertinent arboviruses, they forwarded the specimens to the
C.D.C., Dr. Gubler said.
Dr. Gubler said scientists also needed to investigate whether the deaths of the birds
indicated that West Nile virus had become more virulent.
Also, the virus has been shown to stay in the blood of humans longer than other types
of encephalitis virus, so that mosquitoes are more likely to pick it up and transmit it to other
humans. But whether such transmissions occur on a regular basis is not known, Dr. Gubler
said.
A main focus will be to prevent a recurrence of the outbreak in New York next
summer. Scientists do not know whether the virus can persist in infected mosquitoes while
they hibernate over the winter, Dr. Gubler said. In the absence of definitive information,
health officials will consider the need to begin control of storm drains to decrease the
probability of infected mosquitoes' surviving over the winter.
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Socratic Seminar Questions
Use the key terms to create three of each level of question from your two readings during this unit.
Level One: Input Questions
1.
2.
3.
Level Two: Processing Questions
1.
2.
3.
Level Three: Output Questions
1.
2.
3.
P a g e | 219
Guidelines for Participants in a Socratic Seminar
1. Refer to the text when needed during the discussion. A seminar is not a test of
memory. You are not "learning a subject"; your goal is to understand the ideas,
issues, and values reflected in the text.
2. It’s OK to "pass" when asked to contribute.
3. Do not participate if you are not prepared. A seminar should not be a bull session.
4. Do not stay confused; ask for clarification.
5. Stick to the point currently under discussion; make notes about ideas you want to
come back to.
6. Don't raise hands; take turns speaking.
7. Listen carefully.
8. Speak up so that all can hear you.
9. Talk to each other, not just to the leader or teacher.
10. Discuss ideas rather than each other's opinions.
11. You are responsible for the seminar, even if you don't know it or admit it.
Expectations of Participants in a Socratic Seminar
When evaluating each other, and when your teacher is evaluating your participation, the following
questions are addressed:
Did you…
Speak loudly and clearly?
Cite reasons and evidence for their statements?
Use the text to find support?
Listen to others respectfully?
Stick with the subject?
Talk to each other, not just to the leader?
Paraphrase accurately?
Ask for help to clear up confusion?
Support each other?
Avoid hostile exchanges?
Question others in a civil manner?
Seem prepared?
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Socratic Seminar Observation Form
Inner-Outer Discussion Circle
Your Name:
Partner:
SPEAKS IN THE DISCUSSION:
LOOKS AT PERSON WHO IS SPEAKING:
REFERS TO THE TEXT:
ASKS A QUESTION:
RESPONDS TO ANOTHER SPEAKER:
INTERRUPTS ANOTHER SPEAKER:
ENGAGES IN SIDE CONVERSATION:
AFTER DISCUSSION: What is the most interesting thing your partner said?
AFTER DISCUSSION: What would you like to have said in the discussion?
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Warm Up: Are Viruses Alive?
List the characteristics of life and the points of the cell theory. Then, write a paragraph explaining
whether you think viruses are alive or not. Use the characteristics of life to defend your opinion.
Characteristics of Life:
Virus Notes
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Cell Theory:
Virus Notes
What is the basic
definition of virus?
______________: Submicroscopic, parasitic, acellular entity composed of a
nucleic acid core surrounded by a protein coat.
– Below the resolution of a ______________________________
– Relies on a __________________________
– Does not have the properties of ______________________________
– Viruses are measured in ___________________________________
• 0.000000001m or 10-9
What is the structure
of viruses?
Although viruses can have several shapes, all have at least two parts:
• An outer ________________________ made of proteins.
• ________________________________________ (DNA or RNA – never both)
1. ______________________________________________
What are some
examples of viral
structures?
What is a
bacteriophage?
Why aren’t viruses
considered
_________________?
What are the two
ways that viruses can
reproduce?
The virus that causes the common cold.
2. ______________________________________________
The virus that causes the flu.
3. ______________________________________________
A virus that infects bacteria.
4. _______________________________________________
A virus that causes disease in tobacco leaves.

A virus that invades bacteria. It consists of a ____________________________
and a _________________________________________.





Viruses are __________________ (___ cells)
Viruses have no ______________________ to take in nutrients or use energy.
Viruses cannot make ______________________________.
Viruses cannot ____________________.
Viruses cannot ________________________________ on their own.
Viruses reproduce by infecting other cells.
Two types of viral infections:
1. ________________________________________________________
2. ________________________________________________________
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Virus Notes
226 | P a g e
Virus Notes



What are the steps of
a lytic infection?


What are some
characteristics of
lytic infections?
What are the steps of
a lysogenic
infection?
__________________________________________________________________________
__________________________________________________________________________
Ex. _______________________________________________________________________



Step 1: Virus ___________________ and inserts its DNA inside host
Step 2: Viral DNA ___________________to the host DNA (____________ DNA)
Step 3: The viral DNA lies ___________________ and its DNA replicates
each time the cell divides
Step 4: Stress or other “factors” causes the infection to progress to
the _______________ phase





What is a retrovirus?




What are some
characteristics of
lysogenic infections?

Step 1: ______________________of virus to host cell
Step 2: ____________________ of viral DNA into cell
Step 3: _____________________of viral DNA and Synthesis of Protein
Capsule using cellular “machinery”
o (enzymes, ribosomes, etc.)
Step 4: __________________ of new viruses inside host cell
Step 5: New viruses ________________ the host cell and are released for
further infection
__________________________________________________________________________
__________________________________________________________________________
__________________________________________________________________________
Ex. _______________________________________________________________________
A retrovirus is a virus with _______________ rather than DNA for its genetic
material.
These viruses carry an ________________________ to create DNA from their
RNA. The viral DNA then integrates into a chromosome.
Summary:
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Retrovirus
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Lytic & Lysogenic Cycles
For each number, identify it as part of the lytic or lysogenic cycle and describe what is happening.
1.
2.
3.
4.
5.
6.
7.
8.
9.
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Viral Replication Foldable
Refer to page 515 in your textbook for directions on making a viral replication foldable. Attach your
foldable onto this page.
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Warm Up: Influenza Epidemics
There were three worldwide influenza epidemics during the twentieth century. The number of
deaths is presented in the table below.
Spanish Flu
Asian Flu
Hong Kong Flu
Years
1918-1919
1957-1958
1968-1969
U.S. Deaths
500,000
70,000
34,000
Global Deaths
20-40 million
1 million
1-4 million
1. Which epidemic was the most deadly?
2. Why were deaths not as high in the United States with the Hong Kong flu compared to the Asian
flu, but were higher worldwide?
3. Hypothesize why a flu epidemic eventually stops instead of eliminating all human life.
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Comparing Bacteria & Viruses
Bacteria
Viruses
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Microbiology Unit Concept Cards
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Microbiology Unit Concept Map
(see directions on page 21)
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Parent/ Significant Adult Review Page
Student Portion
Name _________________________________________________
Unit Summary (write a summary of the past unit using 5-7 sentences):
Explain your favorite assignment in this unit:
Adult Portion
Dear Parent/ Significant Adult:
This Interactive Notebook represents your student’s learning to date and should contain
the work your student has completed. Please take some time to look at the unit your
student just completed, read his/ her reflection and respond to the following
Ask your child to describe why viruses are considered “non-living”. Write a few points from
your discussion below:
Areas my student could improve are:
Parent/ Significant Adult Signature:
Comments? Questions? Concerns? Feel free to email their teachers.
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Socratic Seminar Reflection
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Microbiology Unit Study Guide
1. List three differences between gram + and gram - bacterium.
•
•
•
3. If the spirilla bacteria above are stained pink, this indicates that
____________________________________________________________________________________________.
4. If the cocci bacteria above are stained purple, this indicates that
____________________________________________________________________________________________.
5. When a bacterium is in a stressful or unfavorable environment it enters a _______________ state. It
forms a structure called the _________________________, which encloses its _______________ and part of
its ______________________.
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Microbiology Unit Study Guide
6. A person is infected with a virus. Create a graph of body temperature over time that shows how
a lytic virus would progress, and then create another graph that shows how a lysogenic virus
would progress.
Give a short explanation to defend each graph.
7. Contrast conjugation and binary fission using the table below. How are they different?
Conjugation
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Binary Fission
Microbiology Unit Study Guide
8. Penicillin attacks the _____________________________in the ___________ __________ of ___________
_____________________bacteria.
9. Whereas, ciproflaxin disrupts _____________________ __________________ at the ribosomal level,
therefore is typically used against _______________ ______________bacteria.
10. Label the type of bacterial cell well and the parts of the cell wall in the diagram below using the
following terms: inner membrane, outer membrane, peptidoglycan, membrane protein, inside the
cell, and outside the cell.
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Microbiology Unit Study Guide
11. Compare and contrast lytic and lysogenic infections.
Things to know for Microbiology Unit Test
 How bacteria form spores and the scientific terms used to describe the process.
 Bacteria shapes and scientific names to describe the shapes.
 Structure of Gram negative and Gram positive bacteria cell walls (what makes up the
different cell walls?).
 Be able to name the parts of the cell wall and cell membrane of bacteria, and the function of
each part.
 Know what makes up peptidoglycan, know the different proteins in the cell membrane and
their functions.
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Microbiology Unit Study Guide
Things to know for Microbiology Unit Test (continued)
 Which antibiotics (penicillin and ciproflaxin) are used to treat which type of bacteria (Gram
negative or Gram positive).
 The different ways in which bacteria divide.
 Understand the concept of exponential growth and be able to read an exponential growth
curve (157).
 Understand the basic concept of the antiseptic comparison lab. Be able to explain what a
round paper with a halo and without a halo means.
 The structure of a virus (what are its parts?).
 Types of viruses and which organism they infect.
 Know the characteristics about the retrovirus.
 Know exactly what happens at each step of the lytic and lysogenic cycles (page 193).
 Know the characteristics of the lytic and lysogenic cycles (virus notes).
 Know the differences and similarities of viruses and bacteria (198).
 Know the meaning of scientific terms used to describe virus infection of a host, such as
prophage (virus notes).
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Microbiology Unit Back Page
The California State Standards I have come to use and understand are:
 Students know how prokaryotic cells, eukaryotic cells (including those from plants and
animals), and viruses differ in complexity and general structure.
 Students know there are important differences between bacteria and viruses with respect
to their requirements for growth and replication, the body's primary defenses against
bacterial and viral infections, and effective treatments of these infections.
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