Microbiology Lab Exam
Study up on you micro, use deduction to determine what bacteria is in your culture. Plus test your memory on the different media
- 1.What are the properties of MSA?
- A.
Salt and Mannitol
- B.
Not selective and egg yolk
- C.
Bile salts and Lactose
- 2.What are the properties of MAC agar?
- A.
Salt + mannitol
- B.
Bile salts + lactose
- C.
Bile salts + egg yolk
- 3.Which of the following are lactose positive, that is turns red or pink on MAC agar?
- A.
Proteus
- B.
Enterobacter
- C.
Shigella
- 4.Which of the following do not ferment lactose, that is turns light brown on MAC agar?
- A.
E. coli
- B.
Klebsiella
- C.
Salmonella
- 5.Which of the following are lactose negative, that is it turns brown on MAC agar?
- A.
Shigella
- B.
Enterobacter
- C.
Klebsiella
- 6.Which of the following is a lactose positive bacteria?
- A.
Klebsiella
- B.
Salmonella
- C.
Proteus
- 7.Does E.coli turn red/ pink on MAC agar, giving a positive reaction?
- A.
True
- B.
False
- 8.Egg yolk contains ___________ which can be broken down into fatty acids by the enzyme ____________
- 9.The control LIA tube tests for?
- A.
Growth
- B.
Glucose fermentation
- C.
Decarboxylation of lysine
- 10.In O/F tubes, if there is growth in both tubes the bacteria is?
- A.
Anaerobice
- B.
Facultative anaerobe
- C.
Aerobic
- 11.In a O/F tube, the tube goes what colour if it can ferment glucose?
- A.
Yellow
- B.
Pink
- C.
Purple
- 12.What colour is the slope of a TSIA tube if the bacteria can utilise lactose and/or sucrose?
- A.
Yellow
- B.
Pink
- C.
Purple
- 13.What colour is the slope of an TSIA tube if the bacteria cannot ferment lactose and/or sucrose?
- A.
Yellow
- B.
Pink
- C.
Purple
- 14.What causes the black precipitate in a TSIA tube?
- A.
Sulphide + iron salt = ferrous sulphide
- B.
Tellurite reduction
- 15.Which media is selective and differential for Corynebacterium?
- A.
HBA
- B.
TBA
- C.
MAC
- 16.If the VP test comes back positive, what is the result of MR?
- A.
Positive
- B.
Negative
- 17.Which combination is true for E.coli?
- A.
Lac +, VP -, CIT +
- B.
Lac -, ONPG +, Urease +
- C.
Lac +, MR +, indole +
- 18.Which are Urease positive?
- A.
E. coli
- B.
Protease
- C.
Salmonella
- D.
Klebsiella
- 19.Which of the following is VP positive?
- A.
E. coli
- B.
Enterobacter
- C.
Proteus
- D.
Salmonella
- E.
Shigella
- F.
Klebsiella
- 20.Shigella and Klebsiella are both motile
- A.
True
- B.
False
- 21.Proteus and Salmonella are both ONPG negative
- A.
True
- B.
False
- 22.Shigella ferment glucose to acid and gas
- A.
True
- B.
False
- 23.Which of the following decarboxylate lysine in LIA tubes?
- A.
E. coli
- B.
Enterobacter
- C.
Proteus
- D.
Salmonella
- E.
Shigella
- F.
Klebsiella
- 24.Which Enteric is the only Indole positive bacteria?
- A.
Enterobacter
- B.
E. coli
- C.
Salmonella
- 25.Which of the following produse H2S?
- A.
E. coli
- B.
Enterobacter
- C.
Proteus
- D.
Salmonella
- E.
Shigella
- F.
Klebsiella