ASCP Microbiology 2

Question 1

Which culture medium is used for isolation of Neisseria gonorrhoeae?

Accepted Answer

Thayer-Martin agar

Answer

MacConkey agar

Answer

Mannitol salt agar

Answer

TCBS agar

Question 2

Acid-fast bacilli seen on Ziehl-Neelsen stain are most consistent with:

Accepted Answer

Mycobacterium tuberculosis

Answer

Clostridium difficile

Answer

Nocardia asteroides only

Answer

Bacillus anthracis

Question 3

A positive oxidase test (purple color) differentiates which organism from Enterobacteriaceae?

Accepted Answer

Pseudomonas aeruginosa

Answer

Staphylococcus aureus

Answer

Escherichia coli

Answer

Enterococcus faecalis

Question 4

Which toxin produced by Clostridium difficile causes pseudomembranous colitis?

Accepted Answer

Toxin A (enterotoxin) and Toxin B (cytotoxin)

Answer

Exotoxin A only

Answer

Endotoxin

Answer

Shiga toxin

Question 5

India ink preparation is used to visualize the capsule of which organism in CSF?

Accepted Answer

Cryptococcus neoformans

Answer

Haemophilus influenzae

Answer

Neisseria meningitidis

Answer

Listeria monocytogenes

Question 6

Which antibiotic resistance mechanism involves enzymatic destruction of the beta-lactam ring?

Accepted Answer

Beta-lactamase production

Answer

Efflux pumps

Answer

Target site modification (altered PBPs)

Answer

Decreased outer membrane permeability