Micro Mischief
Midterm 2008
1) Bacillus Anthrasis can be caught by:
a. Skin contact
b. Inhalation, even after years of sporedom
c. Eating undercooked beef from an anthrax infected cow
d. All of the above
2) What makes Bacillus Anthrasis feel all special?
a. Its spores are different than other infectious material in that they enter the
lymphatic tissue
b. It can be identified using an acid fast stain
c. It’s anti-phagocytic capsule is made from D-Glutamate instead of the
usual polysaccharide coat.
d. The gram positive rods appear club shaped or v-shaped
3) Gram negative and gram positive bacteria are different in that:
a. The gram positive bacteria has two layers separating it from the cytoplasm
whereas the gram negative only has one peptidoglycan layer.
b. Gram Positive is more vulnerable to lysozyme and penicillin
c. Gram Positive contains teichoic acid in its cell wall
d. Both b and c
4) Which one of the following is not a gram positive organism?
a. Salmonella
b. Bacillus anthrasis
c. Streptococcus pyrogenes
d. Clostridium Botulinum
5) Which of the following does not have a cell wall?
a. Mycoplasma
c. Clostridium tetani
c. Staphylococci
d. Bacillus
6) There are 6 classes of gram positive organisms we went over and the rest are gram
negative – pick the six from this list:
a. Streptococcus
b. Enteric
c. Listeria
d. Corynebacterium
e. Zoontic
f. Mycoplasma
g. Staphylococcus
h. Bacillus
i. Clostridium
j. Neisseria
7) Which one of the below is not part of our normal flora?
a. Escherichia coli
b. Staphylococcus saprophyticus
c. Lactobacillus
d. Enterocolitis
8) All of the following are used for macroscopic classification of microbes except:
a. Shape, size and color
b. Smooth and rough variants
c. Stained samples
d. All of the above are macroscopic
9) You need to diagnose an illness right away. Which biotyping method would you
not use?
a. PCR
b. Measuring the ability to ferment glucose
c. Serological methods
d. Testing phage specificity
10) Which of the following is a rod-like shape?
a. Staphylococcus aureus
b. Spirochete
c. Shigella
d. None of the above are rod-shaped, (bacillus)
11) A few weeks after a baby was born, she developed meningitis. This could be due
to an infection that crossed the placenta caused by:
a. Listeria monocytogenes
b. Clostridium botulinum
c. Bacillus cereus
d. Corynebacterium
12) In lecture 7 there was a slide listing terms to learn. Can you put them in order?
Afebrile serious medical condition characterized by a
whole-body inflammatory state caused by
infection.
Carbuncle A spreading inflammation of subcutaneous or
connective tissue.
Sepsis A usually bacterial infection of bone and bone
marrow in which the resulting inflammation
can lead to a reduction of blood supply to the
bone.
Debrided Wound Redness of the skin caused by dilatation and
congestion of the capillaries, often a sign of
inflammation or infection.
Cellulitis Having no fever.
Fastidious certain enzymes and other compounds dissolve
necrotic tissue.
Pyogenic Muscular pain or tenderness, especially when
diffuse and nonspecific.
Erythematous rash A painful, circumscribed pus-filled
inflammation of the skin and subcutaneous
tissue usually caused by a local staphylococcal
infection. Also called furuncle.
Opsonization an abscess larger than a boil, usually with one
or more openings draining pus onto the skin.
Myalgia The process by which bacteria are altered by
opsonins so as to become more readily and
more efficiently engulfed by phagocytes.
Osteomyelitis Having complicated nutritional requirements.
Boil bacterial infections that make pus or form
abscesses
13) You have a patient who has a gram positive microbe that is alpha hemolytic.
You narrow it down to 2 choices and will then distinguish between the two by:
a. seeing if the microbe is sensitive to Bacitracin
b. testing to find whether the organism is inhibited by optochin
c. trying to grow it in 6.5 % NaCl
d. You’re up the creek without a paddle unless you determine if your sample
is from the throat or the anus.
14) Alpha hemolysis is _____________.
a. greenish darkening of the agar under the colonies due to an incomplete
lysing of RBCs. S. pneumoniae and S. viridans display alpha hemolysis
b. caused by a complete lysis of the red cells in the media. The area around
and under the colonies are lightened and transparent. S. pyogenes and S.
agalactiae display alpha hemolysis.
c. A yellowish tint surrounding colonies as an indicator of the ability to
produce H2S on blood agar plates. S. pneumoniae and S. viridans display
alpha hemolysis.
d. A green/yellow area produce on blood agar plates as a result of complete
hemolysis. S. pyogenes and S. agalactiae display alpha hemolysis.
15) You’re working on serologically identifying an organism suspected of being
salmonella. After you add the primary that would adhere to it’s flagella, you see
an itty-bitty baby that distracts you from adding your secondary antibody and
you…
a. See a light pink color
b. Don’t see anything different
c. See the color of the original primary antibody added
d. You see a purple stain
16) A 12 year old boy comes in with red socks and complains of a itchy blisters
around his middle. He’s breathing hard, has a tongue that matches his socks and
basically looks like hell. He also looks like he drinks a lot of milk because he has
a permanent white moustache. Given that you only had half a term of micro
before you saw him, your thoughts are that it could be:
a. Typhoid fever
b. An infection due to Corynebacterium diphtheriae
c. Scarlett Fever
d. Rotavirus
e. Nothing – he’s just a big whiner.
17) For the above case, you figure you should go ahead and treat the boy with:
a. penicillin
b. vancomycin
c. tetracycline
d. an anti-toxin
e. I told you, just send him home with a vegan lollipop.
18) You discover that you have a mysterious plate you’ve been keeping in your CO2
incubator at home – you know, the one with the stir fry in it. Since you have so
much time on your hands you decide to investigate. You discover that it must
have catalase and can live in the open air. It is a gram positive round thing and is
able to undergo beta hemolysis.
a. Streptococcus pyogenes
b. Staphylococcus epidermis
c. Staphylococcus aureus
d. Clostridium botulinum
19) Endospores are formed by these two genera of gram positive bacteria: (pick 2)
a. Clostridium
b. Cornyebacterium
c. Bacillus
d. Enteric
20) Which of the following is not true?
a. A coagulase test will be positive if the organism is Staphylococcus aureus,
but not if it’s Staphylococcus saprophyticus.
b. Penicillin works by blocking the binding of amino t-RNA to the 30S
ribosomal subunit
c. Bacteroids are the most common intestinal bacteria
d. Normal intestinal microflora aid in the development of the immune system
by increasing the numbers of IgA secreting B cells
21) This is an example of group D in the Lancefield Grouping classification system:
a. S. agalactiae
b. S. pyogenes
c. Enterococcus
d. S. pneumoniae
22) Case study; A 7 year old girl has bloody diarrhea and fever (temperature 101
degrees F) but no nausea or vomiting. Only lactose-fermenting colonies are seen
on EMB agar. Your diagnosis is diarrhea caused by:
a. Campylobacter jejuni
b. Enterohemorrhagic strains of E. coli (0157:H7)
c. Shigella
d. Salmonella
e. A and B are both potential candidates for infection
23) Baby Penelope comes home from a week of daycare unpleased. She develops
bloody diarrhea and a fever. You take a blood smear and find leukocytes. Non-
lactose fermenting colonies are seen on the EMB agar. Your diagnosis is diarrhea
caused by:
a. Vibrio cholerae
b. Shigella
c. Enterohemorrhagic strains of E. coli (0157:H7)
d. Klebsiella
e. Cornynebacterium diptheriae
24) A friend comes over bringing a bowl of 2-day old reheated rice and beans to add
to your burrito party. As she prepares to dump the mixture onto the tortilla you
remember your microbiology class and scream,
a. “No! It might contain Bacillus cereus reactivated endospores!!”
b. “Yes! I love a good round of botulism!”
c. “Are you crazy? There could be Bacteroides fragilis in there!!”
d. All of the above since you’re not quite sure.
25) Some old guy comes staggering into the hospital, cusses out the nurse and runs to
the bathroom. He is showing all the signs of food poisoning and your assistant
tells you that she feels that the culprit is an anaerobe. When asked if he had any
rice he bites you. You decide to give him:
a. Nothing; just keep him hydrated
b. An Antitoxin
c. Vancomycin
d. Penicillin
26) A young girl complains of sharp stabbing pains in her abdomen. She thinks it has
something to do with consuming too much alcohol the night before or because she
was riding the mechanical bull in the bar. She says she “about screams” when she
has to pee which is happening more and more frequently. Looking at her sample,
you find round bacteria. You tell her:
a. “Whoa, you need to wipe from front to back or something because you’ve
got e-coli all over you.”
b. “I suspect that you’ve been using tampons from the ‘80’s and I need to
give you some vancomycin.”
c. “Listen, you have a staph infection, o.k.?”
d. “I believe you have contracted leprosy via constant exposure at the shady
bar.”
27) The germ theory is:
a. Terrain is necessary but not sufficient
b. Microbes cause disease
c. Microbes are sufficient, but not necessary
d. Both b and c
28) When you feel sick, it’s usually directly because of:
a. The bacteria – especially when encapsulated
b. Mast cell histamine release
c. T-cell cytokines
d. The bacterial antigen proteins
29) Circle all of the following that can bring on food poisoning:
a. C. Perfringens
b. B. cereus
c. C. botulinum
d. A. aureus
30) You have a rural practice and the local heroine addict, Harold, comes into your
clinic with a slimy coating around his inguinal area. You try not to act shocked
and take a sample. When you pour hydrogen peroxide on it, it makes bubbles.
Then you slap it in some bunny plasma and after incubating it for an hour, nothing
is happening to it.
a. Harold has S. epidermitis
b. Harold has campylobacter
c. Harold has M. tuberculosis in his lymph system
d. You cannot tell what he has until after a hemolysis test
31) All but the following are true of non-inflammatory diarrhea:
a. Responds to non-absorbable antimicrobials
b. There’s not a lot of pain, but there is a lot o’ water
c. There are no PMN in stool
d. Bacteria multiply in the ileum and colon
32) A patient comes in with bloody diarrhea. Only knowing this, what could it be?
a. Shigella enterocolitis
b. V. Cholera
c. C. difficile
d. Enteroinvasive E-Coli
e. Enterotoxigenic E-Coli
f. Enterohemmorragic E-Coli
g. Campylobacter
h. Heliobacter pylori
i. Klebsiella
j. Bacteroides fragilis
33) You now find that the above diarrhea case, (32), is rod-like, stains pink. Which
are no longer options?
34) You find out that the diarrhea case, (32), does not ferment lactose and produces
H2S gas. Can you figure it out?
35) A patient comes in with heart problems. Only knowing this, what could a bug be?
a. S. aureus
b. S. faecalis
c. S. pyogenes
d. S. mutans
36) All of sudden, God comes down and tells you that the above endocarditis blood
sample stains purple and can break down peroxide into oxygen and water. You
look at the organism in the microscope and discover that it is round. What is it?
37) How would you tell the difference between E-coli, Salmonella and Shigella?
a. They are in different locations
b. Shigella produces H2S
c. Salmonella stain purple
d. Ecoli is lactose fermenting, unlike the other 2
38) Which is not an example of a coliform bacteria?
a. Klebsiella
b. V. cholera
c. E. coli
d. Enterobacter
e. Serratia
f. Proteus
39) Which is not spore forming?
a. B. cereus
b. C. difficile
c. C. diphtheriae
d. C. tetani
40) What in the world is a Lancefield Group? (still writing a little)
a. A way of categorizing Staphylococci
b. A method using PCR to decipher between Streptococcus strains
c. An out of date method of culturing Strep. On different media
d. A serological method of grouping based on polysaccharide components.
41) Why wouldn’t you just culture TB instead of spending all the money to run a
PCR?
a. Because the niacin can only be detected with the PCR method
b. Because it takes two weeks to culture
c. Because it is not able to be cultured
d. None of the above
42) A man comes wandering complaining of chest pain, constant cough and has a
fever. You want to use your new machine so you run a chest X-ray and find that
he has TB, (o.k., you may have done the skin test, but whatever). His X-ray could
have:
a. a hazy right lung with hilar lymphadenopathy
b. a bilateral opacity
c. a bilateral infiltrates that could be fibrotic
d. Both a and c
43) Of these gram positive rods, which is a strict anaerobe?
a. Bacillus
b. Clostridium
c. Cornyebacterium
d. Listeria