Download biobugs - Boston University

BUCDC
Center for Disease Control
@ Boston University
BUCDC
Welcome
• B.U.C.D.C is the Boston University Center
for Disease Control
• Founded: 1968
• Mission: The storage and study of
pathogenic agents for the purposes of
understanding disease transmission in
order to control and eradicate potential
outbreaks
BUCDC
B.U.C.D.C. Staff
• Director of Pathogen Storage: Jan Blom
• Director of Laboratory Safety: Matthew Walker
• Director of Technology Support: Xiaojuan
Khoo
• Technical Assistants:
– Derek Stefanik
– Ysabel Milton
– Kevin Yu
– Angela Seliga
BUCDC
Lab Safety
http://www.mbio.ncsu.edu/MB451/lab/labSafety.jpeg
BUCDC
Lab Safety:
What’s So Dangerous?
Pathogenic: “To cause
disease”
• Pathogenic Agents
– Bacteria: Necrotizing
Fasciitis, TB, Diptheria,
Anthrax
– Viruses: Swine Flu,
Measles, Mumps, AIDS
– Parasites: Tape worm,
Guinea worm, Flea,
Hook worm
– Prions: Kuru,
Creutzfeldt-Jakob
Disease (CJD)
BUCDC
Lab Safety: Eliminate the
Transmission of Disease
• Communicable Disease: Can
pass between individuals
– Cutaneous
• Direct skin to skin contact is required
for transmission
• Anthrax, Athletes Foot
– Ingestion
• Transmission occurs when then the
pathogenic agent is eaten
• Kuru, Tape worm
– Bodily fluid
• Direct contact with the following fluids
is required: saliva, blood, lymph, urine
• AIDS, Hepatitis
– Inhalation
• Agent is airborne enters via the lungs
• SARS, Influenza, The common cold
BUCDC
•
Lab Safety Guidelines (Pg. 3-4)
Primary Goals
1. Protect researcher from the sample
2. Protect the sample from the researcher
•
Physical Barriers
– Lab coats
– Gloves
– Tie hair back
BUCDC
•
Lab Safety Guidelines (Pg. 3-4)
Other
–
–
–
–
–
–
No eating/drink/headphones/cell phones
Waste goes into appropriate bins
Report all spills
All backpacks/jackets should be placed on
the counter away from the lab space
Wash all working spaces with 70% ethanol
ASK QUESTIONS IF YOU ARE NOT
SURE!
Refer to the provided Lab Safety Guide and sign
the Lab Safety Contract (Pg. 4) before
proceeding.
BUCDC
Lab Safety Quiz: What is
Unsafe About These Pictures?
BUCDC
What is Unsafe About This
Picture?
http://www.chem.unl.edu/chwang/orgsafety/jun17_12.jpg
BUCDC
What is Unsafe About This
Picture?
BUCDC
What is Unsafe About This
Picture?
Trash
BUCDC
BUCDC Ice Breaker!
• Put on lab coat,
gloves
• Touch powder
• Blot hand
• Shake hands with
assigned individual
• Blot hand on paper
• Repeat
FOLLOW THE
DIRECTIONS AS THEY
ARE GIVEN TO YOU
BUCDC
BUCDC Ice Breaker – Lab
Safety
• Put on lab coat and gloves
– Note your ID number
1
• Dispose of gloves in generic waste
• DO NOT DISCARD THE PAPER
TOWELS WITH HAND PRINTS!
BUCDC
BUCDC Ice Breaker
Your Station
Towel 1
Towel 2
Towel 3
White Powder
Towel 4
BUCDC
Step 1: Place RIGHT HAND in
powder
Powder
• Rub hands together, making sure you get lots of
powder on your RIGHT hand.
• Make sure you stand away from table – DO NOT
CONTAMINATE your work bench and materials.
BUCDC
Step 2: Make a handprint and
write down your ID#
Self Test
Write your ID#
Use your RIGHT hand
- hold for 5 seconds
Round 1
Round 2
Round 3
BUCDC
Step 3: Series of Handshaking
• For each Round
– Shake hands for 5 seconds using RIGHT hands
– Make a handprint on towel
• Total of 3 Rounds of Handshaking
• We will tell you who to shake hands with
BUCDC
Round 1 – START!
Shakee’s
Your #
#
1
24
2
23
3
22
4
21
5
20
6
19
7
18
8
17
9
16
10
15
11
14
12
13
13
12
14
11
15
10
Shakee’s
Your #
#
16
9
17
8
18
7
19
6
20
5
21
4
22
3
23
2
24
1
•
•
•
•
Stand up
Find assigned “Shakee”
Stand by “Shakee”
Shake hands for 5 seconds
– E.g., #1 shake #26
• Return to seat
• Make handprint on next
towel
• Write Shakee’s #
DO NOT TOUCH ANY
OTHER PERSON OR
SURFACE TO AVOID
CONTAMINATION!
BUCDC
Round 1: Make a handprint and
write down Shakee’s #
Round 1
Write
Shakee’s #
Self Test
Your ID#
Round 2
Round
3
BUCDC
Round 2 – START!
Shakee’s
Your #
#
1
12
2
11
3
10
4
9
5
8
6
7
7
6
8
5
9
4
10
3
11
2
12
1
13
24
14
23
15
22
Shakee’s
Your #
#
16
21
17
20
18
19
19
18
20
17
21
16
22
15
23
14
24
13
• Shake hands with your
new assigned “Shakee”
• Make hand print on next
towel
• Write down Shakee’s #
DO NOT TOUCH ANY
OTHER PERSON OR
SURFACE TO AVOID
CONTAMINATION!
BUCDC
Round 2: Make a handprint and
write down Shakee’s #
Round 2
Write
Shakee’s #
Self Test
Your #
Round 1
Shakee’s #
Round
3
BUCDC
Round 3 – START!
Shakee’s
Your #
#
1
8
2
7
3
6
4
5
5
4
6
3
7
2
8
1
9
24
10
23
11
22
12
21
13
20
14
19
15
18
Shakee’s
Your #
#
16
17
17
16
18
15
19
14
20
13
21
12
22
11
23
10
24
9
• Shake hands with your new
assigned “Shakee”
• Make hand print on last
towel
• Write down Shakee’s #
DO NOT TOUCH ANY
OTHER PERSON OR
SURFACE TO AVOID
CONTAMINATION!
BUCDC
Round 3: Make a handprint and
write down Shakee’s #
Round 3
Self Test
Your #
Round 1
Shakee’s #
Round 2
Shakee’s #
Write
Shakee’s #
BUCDC
After 3 rounds of handshaking…
• Throw out gloves: In generic trash
• Keep paper towels in front of you
Self Test
Your #
Round 1
Shakee’s
#
Round 2
Shakee’s
#
Round 3
Shakee’s
#
BUCDC
WARNING!! WARNING!!!
BUCDC
WARNING
Air Born Pathogen Detected
Initiate Containment
Protocol
Pressurizing Laboratory
Laboratory Sealed
Lock Down Complete
BUCDC
Possible Pathogenic Agents
Bacteria/
Sample #
Symptoms
Prognosis
Mycobacterium
tuberculosis (A)
Severe cough, fever,
inflammation
If left untreated, patient prognosis
is very good
Streptococcus
pneumoniae (B)
Stiffness of the joints, fever,
If left untreated, patient prognosis
severe cough and migraines
is very good
, short of breath
Escherichia coli (C)
Staphylococcus aureus
(D)
Unknown (U)
Fever, lose of equilibrium,
twitching in the extremities
If left untreated, patient prognosis
is very good
Inflammation of the joins,
If left untreated, prognosis is poor
leading to numbness of the
with 98% fatality. Antibiotics
extremities, severe
coughing, blue-black lesions should be administered within 6
hrs.
?
?
BUCDC
Action Plan
• Who was exposed to the
pathogen?
• Who was Patient Zero?
• How is the disease
passed from person to
person?
• What bacteria have we
been exposed to?
• What is the best
treatment for that
pathogen?
BUCDC
Epidemiology - The Basics
Epidemic: When the number of newly
reported cases in a population is larger
then expected
Patient Zero: First known case of disease
• Epidemiologists try to figure out:
How (the disease is transmitted)
When (was it transmitted)
Where (did it start)
What (what is the cause)
Who (has the disease)
BUCDC
Real World Example: Swine Flu
* Last updated on May 2, 2009
BUCDC
Patient Zero to Epidemic
• Known Patient Zeros
– 1854 Baby at Louis
House. Cholera in Soho
– 1915 Mary Mallon
(A.K.A Typhoid Mary).
Typhoid outbreak in
N.Y.C.
– 1976 Mabalo Lokela
Ebola viruses
– 2003 Liu Jianlun. SARS
in Hong Kung
– 2009 swine flu
BUCDC
Patient Zero to Epidemic
• Patient Zero is infected
BUCDC
Patient Zero to Epidemic
• Patient Zero is infected
– Interacts with others,
passes on infection
BUCDC
Patient Zero to Epidemic
• Patient Zero is infected
– Interacts with others
• Patient Zero dies,
neighbors infect
BUCDC
Patient Zero to Epidemic
• Patient zero is infected
– Interacts with others
• Patient Zero dies,
neighbors infect
– Neighbors interact with
others, infecting them
BUCDC
Patient Zero to Epidemic
• Patient zero is infected
– Interacts with others
• Patient zero dies,
neighbors infected
– Neighbors interact with
others, infecting them
• Disease reaches
epidemic levels
BUCDC
Patient Zero to Epidemic
• Patient Zero is infected
– Interacts with others
• Patient Zero dies,
neighbors infected
– Neighbors interact with
others, infecting them
• Disease reaches epidemic
levels
• Response: Isolate those
infected
– Treat or let the disease run
its course
– Quarantine
BUCDC
Who’s infected?
• How do doctors test for bacteria?
– Hint: How do you test for Strep
Throat?
– Take sample, and let it grow
– Problem: Lack of time
BUCDC
Who’s infected?
• How do doctors test for bacteria?
– Hint: How do you test for Strep
Throat?
– Take sample, and let it grow
– Problem: Lack of time
• Fortunately, the bacteria lights up
under black light.
– Use light as a detection method
• Have you been infected?
BUCDC
Action Plan
• Who was exposed to the pathogen?
– 8 people
– We have an outbreak situation
• Who was Patient Zero?
• How is the disease passed from person to
person?
• Which bacteria have we have been exposed to?
• What is the best treatment for that pathogen?
BUCDC
Who is Patient Zero?
How Fast is it Spreading?
• In the worksheet, identify the individuals that are infected
for each round of handshaking. [Pg. 7)
Infected Individuals
Employee ID
Round 3
Round 2
Round 1
Initial
1
1
1
1
1
2
2
2
2
2
3
3
3
3
3
4
4
4
4
4
5
5
5
5
5
6
6
6
6
6
7
7
7
7
7
8
8
8
8
8
9
9
9
9
9
10
10
10
10
10
11
11
11
11
11
12
12
12
12
12
13
13
13
13
13
14
14
14
14
14
15
15
15
15
15
Infected Individuals
BUCDC
Employee ID
Round 3
Round 2
Round 1
Initial
1
1
1
1
1
2
2
2
2
2
3
3
3
3
3
4
4
4
4
4
5
5
5
5
5
6
6
6
6
6
7
7
7
7
7
8
8
8
8
8
9
9
9
9
9
10
10
10
10
10
11
11
11
11
11
12
12
12
12
12
13
13
13
13
13
14
14
14
14
14
15
15
15
15
15
16
16
16
16
16
17
17
17
17
17
18
18
18
18
18
19
19
19
19
19
20
20
20
20
20
21
21
21
21
21
22
22
22
22
22
23
23
23
23
23
24
24
24
24
24
25
25
25
25
25
26
26
26
26
26
Total # Infected
BUCDC
Tracking the infection
26
24
22
20
18
Total #
Infected
16
14
12
10
8
6
4
2
Initial Rd 1
Rd 2
Rd 3
Rd 4
• How quickly does the infection spread?
BUCDC
Tracking the infection
26
24
22
20
18
Total #
Infected
16
14
12
10
8
6
4
2
Initial Rd 1
Rd 2
Rd 3
Rd 4
• How quickly does the infection spread?
BUCDC
Emergency Alert!
We have 2 HOURS to identify the pathogen and find a
cure
BUCDC
Ice Breaker – Discussion (Pg. 8)
• Who is Patient Zero?
• What is the most likely route of transmission?
Explain.
• How would the transmission of the disease
change if it were airborne? Waterborne?
BUCDC
Action Plan
• Who was exposed to the pathogen?
– 8 people
– The rest of the lab will be infected in 2 hours
• Who was Patient Zero?
– The first known infected patient is #5
• How is the disease passed from person to
person?
– Most likely skin to skin contact
• Which bacteria have we have been exposed
to?
• What is the best treatment for that pathogen?
BUCDC
How To Identify Bacteria
• DNA sequencing
– Order of nucleotide (ACGT) varies between
bacteria
• Culture
– Specific bacteria can only grow in certain
environments
• Morphology
– Classify bacteria via shape or other physical
properties
• Physiology (Enzymatic Processes)
– Certain bacteria can carry out different reactions
• Other?
BUCDC
How To Identify Bacteria
• DNA sequencing
– Order of nucleotide (ACGT) varies between
bacteria
• Culture
– Specific bacteria can only grow in certain
environments
• Morphology
– Classify bacteria via shape or other physical
properties
• Physiology (Enzymatic Processes)
– Certain bacteria can carry out different reactions
• Other?
BUCDC
Bacterial Morphology
Staphylococcus aureus, (MRSA)
Neisseria gonorrhoea (Gonorrhea)
Chlamydia trachomatis (Chlamydia)
Coccus
(Round)
Bacillus
(Rod)
Bacillus anthracis (Anthrax)
Bacillus cereus (Food poisoning)
Bacillus subtilis
Escherichia coli,
Mycobacterium tuberculosis
(Tuberculosis )
Spirillum minus (Rat-bite fever)
Treponema pallidium (Syphilis)
Corynebacterium diphtheriae (Diphtheria)
Spirilla
(Spiral)
BUCDC
Two Cocci, What’s the
difference?
Bacteria 1
• Morphology: Coccus
• Pathology: mild cold
Bacteria 2
• Morphology: Coccus
• Pathology: death
BUCDC
Two Cocci, What’s the
difference?
BUCDC
Bacteria Cell Wall Structure
BUCDC
Bacteria Cell Wall - Stained
Strong purple
stain
Gram
Stain
Strong pink stain
BUCDC
Gram positive or negative?
Bacteria Morphology?
Gram Positive (+)
Gram Negative (–)
Coccus
Rod
BUCDC
Stains
bacteria
purple
Gram Stain – The Basics
Helps stain
bind to
peptidoglycan
Gram
Gram positive
positive
stays stained
stained purple
as purple
Gram
negative
unstained
Gram negative
stained pink
BUCDC
Gram Positive or Negative?
BUCDC
Gram Staining – Lab Safety
• Put on lab coat, goggles and gloves
• Place triangle frame over sink/beaker
– All liquids can be emptied down the drain
• Place slides in glass disposal container
• Place gloves in generic waste
BUCDC
Gram Stain - Protocol (Pg. 12-13)
1. Crystal Violet
seconds
4.
90
95% Ethanol
5
seconds
(wash until
colorless)
2. Distilled Water (gentle)
sec
5
3. Iodine
seconds
5. Distilled Water (gentle)
sec
5
6. Safranin
seconds
60
60
Each person in the
group stains one
sample:
7. Distilled Water (gentle)
5
8.
A, B, C, D,
Blot dry without touching bacteriaunknown
BUCDC
Light Microscope (Pg. 10)
Ocular lens
(Eyepieces)
Nosepiece
Objective lenses
(4x – 100x)
Stage Clip
Condenser
Lamp
(light source)
Arm
Mechanical Stage
Coarse Focus (large)
Fine Focus (small)
Illuminator control
(brightness)
Base
Always carry a microscope with one hand
holding the arm and one hand under the base.
BUCDC
Power of Magnification
To calculate the power of magnification, multiply the power of
the ocular lens by the power of the objective.
What are the powers of
magnification for each of
the objectives we have on
our microscopes?
Fill in the table in
your worksheet. (Pg. 11)
BUCDC
Power of Magnification
We can see better details with higher
the powers of magnification, but we
cannot see as much of the image.
Which of these images
would be viewed at a
higher power of
magnification?
BUCDC
Gram Stain - Protocol (Pg. 12-13)
1. Crystal Violet
seconds
4.
90
95% Ethanol
5
seconds
(wash until
colorless)
2. Distilled Water (gentle)
sec
5
3. Iodine
seconds
5. Distilled Water (gentle)
sec
5
6. Safranin
seconds
60
60
Each person in the
group stains one
sample:
7. Distilled Water (gentle)
5
8.
A, B, C, D,
Blot dry without touching bacteriaunknown
BUCDC
Looking at the Gram Stains
(Pg. 13-14)
1. Use the microscope to view Gram stained slides under various objectives:
 4x – tiny specks/spots
 10x – faint smear of colored spots
 40x – start to see shape better
2. STOP. Raise your hands at this point.
3. A volunteer will help you set up oil immersion using the 100x objective.
4. Draw and label all FIVE bacteria samples using the 10x and 100x
objectives.
1. The colors and shapes should be as accurate as possible
2. Determine if the bacteria are Gram positive or Gram negative.
BUCDC
Gram Stain
Discussion (Pg. 16)
• What characteristics can be determined using a
Gram stain?
• What can happen to make Gram positive cells
appear Gram negative?
BUCDC
Two Cocci, What’s the
difference?
Bacteria 1
•
•
•
•
Morphology: Coccus
Gram+
Pathology: mild cold
Differences in
Physiology –
Protein A
Bacteria 2
•
•
•
•
Morphology: Coccus
Gram+
Pathology: death
Differences in
Physiology –
Protein B
BUCDC
Catalase Test – The Basics
• Identify differences in the physiology of bacteria
• Catalase: Enzyme
• Function: To remove toxic byproducts
• Chemical reaction:
2
+
2
Hydrogen Peroxide (liquid)
• No bubbles = negative for catalase
• Bubbles = positive for catalase
Water (liquid)
Oxygen (gas)
BUCDC
Catalase Test
BUCDC
Catalase Test – Lab Safety
• Put on lab coat, goggles and gloves
• Hydrogen peroxide is corrosive
• Place wooden stick and gloves in generic waste
• Place slides in glass disposal container
• Return Petri dishes to instructors
BUCDC
1.
2.
Catalase Test - Protocol (Pg. 18)
Using a wooden stick, smear a small amount of bacteria
from the Petri dish onto a clean microscope slide
Label the slide using the Sharpie marker
Transfer
bacteria
Bacteria
dish
B
BUCDC
1.
2.
3.
4.
Catalase Test - Protocol (Pg. 18)
Using a wooden stick, smear a small amount of bacteria
from the Petri dish onto a clean microscope slide
Label the slide using the Sharpie marker
Add 3 drops of H2O2 solution onto the smear.
Record your observations in the worksheet (Pg. 19).
Transfer
bacteria
3 drops
Bacteria
dish
A
A
BUCDC
1.
2.
3.
4.
5.
6.
Catalase Test - Protocol (Pg. 18)
Using a wooden stick, smear a small amount of bacteria
from the Petri dish onto a clean microscope slide
Label the slide using the Sharpie marker
Add 3 drops of H2O2 solution onto the smear.
Record your observations in the worksheet (Pg. 19).
Repeat steps 1-4 for all FIVE bacteria samples, using new
materials each time.
When done, dispose of materials in the correct bins
Transfer
bacteria
3 drops
Bacteria
dish
A
A
BUCDC
Catalase Test – Discussion (Pg. 19)
•
Which bacteria tested positive for catalase?
Which tested negative?
•
What is the purpose of using new glass slides
and sticks for each bacteria species?
BUCDC
Cracking the Case
• Fill out the summary table in your worksheet (Pg. 21):
Bacteria
Sample
Scientific Name
Morpholog
y
Gram
Staining (+/-)
Catalase
test (+/-)
A
B
C
D
Unknown
Scientific names of given bacteria samples
A – Mycobacterium tubercolosis
B – Streptococcus pneumoniae
aureus
C – Escherichia coli
D – Staphylococcus
BUCDC
Identifying the Unknown
Pathogen – Discussion (Pg. 21)
• Write a 1 paragraph summary describing the
characteristics of the unknown pathogen.
• By comparing these characteristics to known bacteria
samples, A-D, we have identified the unknown pathogen
that has infected our facility as:
_________________________.
Sample D: Staphylococcus
aureus
BUCDC
Action Plan
• Who was exposed to the pathogen?
– 8 people
– The rest of the lab will be infected in 2 hours
• Who was Patient Zero?
– The first known infected patient is #5
• How is the disease passed from person to
person?
– Most likely skin to skin contact
• Which bacteria have we have been exposed
to?
– Gram positive cocci
– Catalase positive
– Bacteria is Staphylococcus aureus
• What is the best treatment for that pathogen?
BUCDC
Potential Treatments
• Suggestions?
BUCDC
How do Antibiotics Kill?
• Antibiotic: “against life”
• Derived from natural products
• Attack specific parts of the cell
Cell Wall
DNA
Cell Membrane
DNA to RNA
RNA to Protein
(Transcription) (Translation)
BUCDC
Example: Neosporin
• Contains:
– Bacitracin
• Attacks the cell wall
(gram+)
– Neomycin
• Binds to ribosome,
prevents translation
– Polymyxin B
• Binds to and disrupts
cell membrane (gram-)
Why so many different drugs in
one?
BUCDC
Antibiotic Testing
Layer of Bacteria
Antibiotic disk
(contains
drug)
Zone of inhibition
Why is there a clear zone immediately around the
antibiotic disk?
BUCDC
Zone of Inhibition
• Compare diameters of
the zones of inhibition
to classify bacteria as:
– R: resistant
• Small/no zone of inhibition
– I: intermediate
• Small to medium zone of
inhibition
Antibioti
c1
Antibiotic
2
Antibiotic
3
Antibiotic
5
Antibiotic
4
– S: susceptible
• Large zone of inhibition
What conclusions can you draw from the above
picture?
BUCDC
Antibiotic Testing – Lab
Safety
• Put on lab coat and gloves
• Place gloves in generic waste
• Return plates to instructor
BUCDC
Antibiotic Testing – Protocol (Pg.
24)
• Use a ruler to measure the zone of inhibition for
the three antibiotics that we are testing.
– Take two measurements per antibiotic disk
• Fill in the table in the worksheet (Pg. 25)
Drug X
Drug Y
Drug Z
BUCDC
Antibiotic Testing – Discussion (Pg.
25)
• Determine if the bacteria is resistant,
intermediate or susceptible to each of the
three antibiotics.
• Which antibiotic has the most potential for
treating the infectious disease?
BUCDC
Course of Action Completed
• Who was exposed to the pathogen?
– 8 people
– The rest of the lab will be infected in 2 hours
• Who was patient zero?
– The first known infected patient is #5
• How is the disease passed from person to person?
– Most likely skin to skin contact
• Which bacteria have we have been exposed to?
– Gram positive cocci
– Catalase positive?
– Bacteria is Staphylococcus aureus
• What is the best treatment for that pathogen?
– Recommended antibiotic is Drug Y (Ampicillin)
BUCDC
ALERT
Air Sampling – No Pathogen
Detected
Treatment Protocols Successful
- Antibiotics administered
Quarantine No Longer Necessary
Lab Lockdown Terminated
Outbreak Contained and Eliminated
BUCDC
Outbreak...Contained
• Summarize what we did today
• Conclusions
• Why is this important?
BUCDC
We hope you enjoyed
BIOBUGS!
Fill out evaluation
survey.
Lunch is served at 12
pm in Room 352.
Panel discussion will
start at 12:25 pm.
BUCDC
For reference: Handshake partners will
change depending on student numbers
Round 1
Shakee’s
Your #
#
1
15
2
14
3
13
4
12
5
11
6
10
7
9
8
8
9
7
10
6
11
5
12
4
13
3
14
2
15
1
Round 2
Shakee’s
Your #
#
1
7
2
6
3
5
4
4
5
3
6
2
7
1
8
15
9
14
10
13
11
12
12
11
13
10
14
9
15
8
Round 3
Shakee’s
Your #
#
1
3
2
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3
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BUCDC
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What are the two primary goals of lab safety?
A student is working with a rob shaped, gram + bacteria. (S)he puts a small amount of liquid containing that bacteria on a plate and places it in an incubator to
grow. The following day, the plate yields both gram + and – cells. What happened to the sample?
Even if a sample is not harmful to the scientists why should they always wears gloves?
In the outbreak scenario, when the pathogen was detected, the lab was pressurized to BELOW atmospheric pressure. Why is this so? (HINT: which direction will the
air flow?)
Assuming the bench top is clean, how could you test to see if any bacteria/contamination is present after it was cleaned?
How does the advent of modern travel (cars/airplanes/trains/boats) influence the outbreak of a disease? (HINT: review the case of the TB patient traveling to
Europe)
Name three methods that a disease can be transmitted. How are they similar? How are they different?
During the Spanish Flu pandemic of 1918, those with the disease were isolated from the rest of the population. What is this called?
How would geographical boundaries such as rivers and mountains protect against the spread of a disease?
How would the time that a infection takes to kill a carrier influence the spread of that pathogenic agent. (HINT: compare and contrast what would happen if the
patient dies within 2 hours of infection, versus one that may not die for 2 years) What are the two primary components of the peptidoglycan layer?
Draw and label a gram-positive and gram-positive cell to scale.
Which cell (gram-positive or gram-negative) shows the color of the COUNTER stain? What is the purpose of this counter stain?
Why is staining required to tell if a cell is gram+ or gramLabel and draw the 3 types of bacterial morphology.
How do is magnification of a microscope calculated
When using a high powered objective, only the fine focus knob should be used, why?
What is the clinical value of the gram staining protocol
Draw the reaction (starting with hydrogen peroxide) that catalase is involved it. Label the states of each reactant and product.
What is the purpose of the catalase enzyme in cells? (HINT: Where does the hydrogen peroxide come from?)
In which organelle is catalase mostly likely found in human cells?
Catalase like many enzymes is temperature dependent. How would you design an experiment to test the activity of this enzyme? Assuming you are using catalase
isolated from human livers, at which temperature do you think the enzyme would be most efficient? Draw a graph of enzyme activity versus temperature
Catalase is an enzyme; therefore what is it made of?
Catalase is present in ALL animals and in all tissues. Furthermore, it has nearly identical structures. Comment on the evolution history of this enzyme, when and
where did it List 2 targets of an antibiotic
Neusporin contains 3 different antibiotics, what is the benefit
Why don’t antibiotics work for a viral infection?
Draw a plate with 3 antibiotic disks. Describe what is happen to the bacteria in the region of each disk
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Disk 1 resistant,
Disk 2 susceptible
Disk 3 intermediate
When a doctor prescribes antibiotics, it is strongly recommended that the patient take the entire dosage, even if they begin feeling better. Why is this important
When dealing with a patient that has a bacterial infection, doctors usually prescribe older antibiotics first. Newer drugs are reserved for the most serious patients,
why is this necessary?