How to use the API Strips 2012
Quiz: What can you remember about API system?
(Answers are listed at the end).
1. What type of bacteria may be identified using the API 20E strip?
a.
b.
c.
d.
Enterobacteriaceae
Staphylococci
Anaerobes
All of the above
2. What two tests are usually performed prior to API 20 E strip to confirm the
microbe is a member of the Enterobacteriaceae?
a.
b.
c.
d.
Oxidase and catalase
Gram’s staining and oxidase
Oxidase and coagulase
Catalase and coagulase
3. What is the purpose of filling the bottom tray of the API strip holder with water?
a.
b.
c.
d.
To dissolve reagents
To provide a humidified chamber for the biochemical tests
The bottom tray of the API strip holder does not need to be filled with water
None of the above
How to use the API Strips 2012
4. Why do some of the biochemical tests require oil to be added to the cupule?
a.
b.
c.
d.
Introduces anaerobic conditions
Stops the end gaseous products of certain reactions to be released
To prevent unwanted reactions
All of the above
5. In what conditions are the API 20E strips incubated?
a.
b.
c.
d.
37°C for 18-24h aerobically
32°C for 24-48h aerobically
37°C for 18-24h anaerobically
22°C for 2-3 days aerobically
6. What does the API abbreviation stand for?
a.
b.
c.
d.
Advance Profile Index
Applied Profile Information
Analytical Profile Index
None of the above
7. What may the negative result for glucose test on the API 20E strip indicate?
a.
b.
c.
d.
The tested organism did not grow in this microtube
The tested bacterium is not from the Enterobacteriaceae family
The tested bacterium belongs to Enterobacteriaceae
Both a and b are correct
8. How would you interpret the result for the IND test on the following API 20E strip?
a. Positive (+)
b. Negative (-)
c. Invalid (required to be repeated)
How to use the API Strips 2012
9. How would you interpret the result for the VP tests on the following API 20E
strips?
1
2
a.
b.
c.
d.
Both Positive (+)
1 Positive and 2 Negative (-)
Both Negative
None of the above
10. How would you interpret the result for the GEL test on the following API 20E
strip?
a. Positive (+)
b. Negative (-)
c. Invalid (requires to be repeated)
How to use the API Strips 2012
11. How would you interpret the result for the ODC tests on the following API 20E
strip?
a. Negative (-)
b. Positive (+)
c. Invalid (requires to be repeated)
12.
Some of the tubes of the API 20E strip need to be filled with the bacterial
suspension right to the very top end including the cupule area. Which are these
tubes?
a.
b.
c.
d.
CIT, H2S, VP
ADH, CIT, VP
ADH, LDC, ODC
CIT, VP, GEL
13. The following tubes (ADH, LDC, ODC, H2S, URE) are underlined. Why?
a. These tubes are required to be filled with the bacterial suspension at the top
area (cupule)
b. These tubes are required to have oil added at the top (cupule)
c. The tests within these tubes require anaerobic conditions
d. Both b and c are correct
14. What colour change may indicate a positive (+) reaction for the glucose test on
the API 20E strip?
a.
b.
c.
d.
Blue to orange
Blue to yellow
Yellow to blue
Green to blue
How to use the API Strips 2012
15. The results for the API 20E strip test are recorded on the results sheet and the
final profile number is obtained. How many digits does that profile number have?
a.
b.
c.
d.
7
5
6
8
ANSWERS
1. What type of bacteria may be identified using the API 20E strip?
e.
f.
g.
h.
Enterobacteriaceae (correct answer)
Staphylococci
Anaerobes
All of the above
2. What two tests are usually performed prior to API 20 E strip to confirm the
microbe is a member of the Enterobacteriaceae?
e.
f.
g.
h.
Oxidase and catalase
Gram’s staining and oxidase (correct answer)
Oxidase and coagulase
Catalase and coagulase
3. What is the purpose of filling the bottom tray of the API strip holder with water?
e. To dissolve reagents
f. To provide a humidified chamber for the biochemical tests (correct
answer)
g. The bottom tray of the API strip holder does not need to be filled with water
h. None of the above
4. Why do some of the biochemical tests require oil to be added to the cupule?
e.
f.
g.
h.
Introduces anaerobic conditions
Stops the end gaseous products of certain reactions to be released
To prevent unwanted reactions
All of the above (correct answer)
5. In what conditions are the API 20E strips incubated?
e. 37°C for 18-24h aerobically (correct answer)
How to use the API Strips 2012
f. 32°C for 24-48h aerobically
g. 37°C for 18-24h anaerobically
h. 22°C for 2-3 days aerobically
6. What does the API abbreviation stand for?
e.
f.
g.
h.
Advance Profile Index
Applied Profile Information
Analytical Profile Index (correct answer)
None of the above
7. What may the negative result for glucose test on the API 20E strip indicate?
e.
f.
g.
h.
The tested organism did not grow in this microtube
The tested bacterium is not from the Enterobacteriaceae family
The tested bacterium belongs to Enterobacteriaceae
Both a and b are correct (correct answer)
8. How would you interpret the result for the IND test on the following API 20E strip?
d. Positive (+) (correct answer)
e. Negative (-)
f. Invalid (required to be repeated)
9. How would you interpret the result for the VP tests on the following API 20E
strips?
1
How to use the API Strips 2012
2
e.
f.
g.
h.
Both Positive (+)
1 Positive and 2 Negative (-)(correct answer)
Both Negative
None of the above
10. How would you interpret the result for the GEL test on the following API 20E
strip?
d. Positive (+) (correct answer)
e. Negative (-)
f. Invalid (requires to be repeated)
11. How would you interpret the result for the ODC tests on the following API 20E
strip?
How to use the API Strips 2012
d. Negative (-)
e. Positive (+) (correct answer)
f. Invalid (requires to be repeated)
12.
Some of the tubes of the API 20E strip need to be filled with the bacterial
suspension right to the very top end including the cupule area. Which are these
tubes?
e.
f.
g.
h.
CIT, H2S, VP
ADH, CIT, VP
ADH, LDC, ODC
CIT, VP, GEL (correct answer)
13. The following tubes (ADH, LDC, ODC, H2S, URE) are underlined. Why?
e. These tubes are required to be filled with the bacterial suspension at the top
area (cupule)
f. These tubes are required to have oil added at the top (cupule)
g. The tests within these tubes require anaerobic conditions
h. Both b and c are correct (correct answer)
14. What colour change may indicate a positive (+) reaction for the glucose test on
the API 20E strip?
e.
f.
g.
h.
Blue to orange
Blue to yellow (correct answer)
Yellow to blue
Green to blue
15. The results for the API 20E strip test are recorded on the results sheet and the
final profile number is obtained. How many digits does that profile number have?
How to use the API Strips 2012
e.
f.
g.
h.
7 (correct answer)
5
6
8