Removal Exam

Question 1

Amino acids used in the test for decarboxylase:

Answer 1

Lysine, Arginine, Ornithine

Question 2

Testing 3 amino acids requires 4 tubes, because:

Answer 2

1 tube is needed for control

Question 3

Enzyme that removes the amino group (NH2) from an amino acid:

Answer 3

Deaminase

Question 4

Organisms that produce urease do what to the medium?

Answer 4

Liquefy the medium

Question 5

Hydrogen sulfide production, other than in TSI agar, requires:

Answer 5

An organic source of sulfure, and a source of metal

Question 6

Negative result in Malonate utilization test:

Answer 6

Green and Yellow

Question 7

Gelatinase breaks down gelatin to:

Answer 7

Amino acids

Question 8

(+) DNAse result after 0.1N HCl is added to the plate:

Answer 8

Agar clears around the colony

Question 9

Urine culture:
Gram (-) rod
Motile
TSI: A/A + gas
Urease (-)
IMVC: +/+/-/-

Answer 9

Escherichia coli

Question 10

Blood culture:
Gram (-) red
Motile, no capsule
TSI: A/A + gas
Urease (-)
IMVC: -/-/+/+

Answer 10

Enterobacter cloacae

Question 11

Blood culture:
Gram (-) rod
Urease (+)
PAD (+)
TSI: K/A + gas
LDC (-), ODC (+)

Answer 11

Morganella morganii

Question 12

Stool culture:
Gram (-) rod
Urease (-)
PAD (-)
TSI: K/A
Nonmotile
LDC (-)

Answer 12

Shigella species

Question 13

Allows viability of acid production by oxidizers in oxidation fermentation (OF) medium:

Answer 13

Peptone content is high

Question 14

Stool culture:
Gram (-) rod
Urease (-)
PAD (-)
TSI: K/A + gas + H2S
Motile
LDC (+)
Indole (+)

Answer 14

Aeromonas hydrophilia

Question 15

Oxidase (+):

Answer 15

Aeromonas hydrophilia

Vibrio cholerae

Question 16

Reagent used for string test:

Answer 16

0.5% sodium desoxycholate

Question 17

Indole (+)
Nitrate reduction (+) is also:

Answer 17

Cholera red (+)

Question 18

Number of oxidation fermentation (OF) media are inoculated and what precautions are taken:

Answer 18

2 tubes, one covered with oil so air is excluded

Question 19

Reason for Thioglycollate broth be boiled for 10 minutes before being used:

Answer 19

To drive off oxygen

Question 20

Clostridia that produces a double zone of hemolysis around colonies on BA:

Answer 20

Clostridium perfringens

Question 21

Mycoplasma pneumoniae is incubated:

Answer 21

Aerobically, in a sealed container in carbon dioxide

Question 22

Urease (+) for Ureaplasma is indicated by a:

Answer 22

Brown halo surrounding colonies

Question 23

Organism that procudes no haze in broth culture:

Answer 23

Ureaplasma urealyticum

Question 24

Serological test done for Chlamydia trachomatis on genital smears:

Answer 24

Direct FA using monoclonal Abs

Question 25

Erythema chronicum migrans (ECM):

Answer 25

Cardinal sign of Lyme disease at site of tick bite

Question 26

Broad spectrum antibiotics:

Answer 26

Acts agrains Gram (-), Gram (+), bacterial, and non-bacterial pathogens

Question 27

Resistance to an antibiotic can be transferred from a resistant to a susceptible organism by:

Answer 27

Extrachromosomal plasmid

Question 28

In Kirby-Bauer ST, the 0.5 MacFarland standard is used to:

Answer 28

Adjust the turbidity of the inoculum

Question 29

After inoculating the MH plates for the KBST, duration should the plates dry before adding the disks:

Answer 29

3 to 5 minutes but not > 15 minutes

Question 30

Measurement of the zone of growth of inhibition for the KBST:

Answer 30

On the underside of the plate
With unaided eye
Using ruler, caliper, or template

Question 31

Too much moisture on the surface of the MH plate when performing KBST:

Answer 31

Smaller zone of growth

Question 32

Best indicators of poor storage:

Answer 32

Penicillin and Methicillin

Question 33

In MH agar, it causes increased resistance of P. aeruginosa to aminoglycosides:

Answer 33

Increased Ca and Mg

Question 34

Two concentric zones around the disk in ST with sulfonamides:

Answer 34

Measure the diameter of the outer zone

Question 35

Lowest concentration of drug that will kill all but the minimum defined proportion of viable organisms after incubation for a fixed time under a given set of conditions:

Answer 35

Minimum Lethal Concentration and Minimum Bactericidal Concentration

Question 36

QC when monitoring reagents, how often should reagent disks be checked:

Answer 36

When container is first opened and weekly

Question 37

How often should catalase, oxidase, and coagulase reagents be tested:

Answer 37

Daily and when vial is first opened

Question 38

Record temperatures of incubators, water baths, heating blocks, refrigerators, freezers, and thermometers:

Answer 38

Every use, at the beginning of each day, at the end of each day

Question 39

Check the face velocity of safety cabinets each:

Answer 39

Month

Question 40

A tube of semisolid medium that has resazurin incorporated in it appears pink. Organism expected to be recovered:

Answer 40

Gardnerella vaginalis

Question 41

True about Clostridia:

Answer 41

Botulism is caused by ingesting preformed toxin and can be prevented by boiling food prior to eating;
Pseudomembranous colitis is due to a toxin produced by C. difficile;
Clinically significant Clostridia are found in the normal flora of the colon and in the soil

Question 42

Anaerobic Gram (-) rod can be presumptively ID by its G/S morphology, growth in the presence of bile, and inhibition by a 1 ug Kanamycin disk:

Answer 42

Fusobacterium nucleatum

Question 43

Purulent material from a cerebral abscess was submitted to the laboratory for smear and culture. On direct G/S, Gram (+) cocci in chains and Gram (-) bacilli with pointed ends were seen. Culture results form this specimen will not be available for 48 hours. Therefore, on the basis of the organisms seen on the smear, what is the most likely presumptive ID of the etiologic anaerobic agents?

Answer 43

Fusobacterium species and Peptostreptococcus species