Microbiology

Question 1

Blood agar
(Enriched/Differential)

Answer 1

Grows most bacteria

Differentiate hemolytic & non-hemolytic

Not best for Neisseria gonorrhoeae

Question 2

Chocolate agar
(Selective)

Answer 2

Enriched with heated RBCs

Grows Neisseria, Haemophilus, and Moraxella

Question 3

Sabouraud agar

Answer 3

Fungi growth
Acanthamoeba

Question 4

Thayer-Martin
(Selective)

Answer 4

Chocolate agar is made selective by adding antibiotics

Isolating Haemophilus and Neisseria

Question 5

Lewenstein-Jehnsen
(Selective)

Answer 5

Special composition and antibiotics to limit growth to Mycobacterium only

Selective for Mycobacterium species e.g. Mycobacterium tuberculosis
Brown granular colonies
‘‘buff, rough, and tough”

Question 6

Thyoglycolate broth
(Enriched/Differential)

Answer 6

Differentiate based on oxygen requirements

For aerobic and facultatively anaerobic bacteria

Question 7

MacConkey agar
(Selective/Differential)

Answer 7

Differentiates based on lactose fermentation

Isolate gram-negative enteric bacilli
Pseudomonas –> Clear colonies
E-coli –> Pink colonies