WorksheetsBiochemical Test
Total questions: 27
Worksheet time: 14mins
Name
Class
Date
1.
A colony of bacteria is placed over a drop of 3% hydrofen peroxide solution immediate oxygen bubbling is observed? What do you say about the bubbling colony of bacterial?
a)
Catalase +ve
b)
Catalase -ve
c)
Lactose fermenting
d)
Gram -ve
2.
In the slide method of the coagulase test, clumping of the organisms is seen within 10 seconds after adding human plasma to one of the suspensions. What is the interpretation?
a)
Coagulase negative
b)
Coagulase positive
c)
Coagulase neutral
d)
Result not clear
3.
At what temperature and duration should the test tube be incubated in the test tube method of coagulase test?
a)
40-47° C for 6 hours
b)
25-30° C for 3 to 4 hours
c)
35-37°Cfor10-12 hours
d)
35-37°C for3to 4 hours
4.
Which of the following test methods are used in the oxidase test procedure?
a)
Filter paper method
b)
Direct plate method
c)
Swab method
d)
All of the method
5.
In the oxidase test, after adding the reagent how long do we need to wait to see the color changes?
a)
10 sec
b)
10 min
c)
1 hrs
d)
1 days
6.
If we are seeing deep purple-blue color after adding reagent in the oxidase test what does that mean?
a)
Positive test
b)
Negative test
c)
Neutral test
d)
No interpretation
7.
Which of the following reagent is NOT used in the oxidase test?
a)
Gordon and McLeod's Reagent
b)
Kovacs Oxidase Reagent
c)
Bromothymol Reagent
d)
Gaby and Hadley (indophenol oxidase) reagent
8.
Which of the following reagent is used in the direct plate method of oxidase test? 1. Kovac's oxidase reagent 2. Covid reagent 3. Gordon and McLeod reagent 4. Jordon and McConkey reagent
a)
1 and 3
b)
1,3and 4
c)
1 and 4
d)
2 and 3
9.
In what type of agar plate the direct plate method of oxidase test is carried out?
a)
Non-selective agar plate [+]
b)
Selective agar plate
c)
Heating plate
d)
Nutrient plates
10.
What is ‘A’ in the following sentence? When using Gordan and Mcleod reagent, microorganisms are oxidased positive whenthe colour changes to "A"
a)
Red within 10 -30 min
b)
Black within 60 minutes
c)
Both A & B
d)
All of the above
11.
What is 'B' in the following sentence? By using the test tube method for the oxidase test, microorganisms are oxidase-positive when the color changes to 'B' within 15 to 30 seconds.
a)
Black
b)
Blue
c)
Brown
d)
Pink
12.
In the test-tube method of oxidase test, the color changes to purple within to 3 minutes. What does it represent?
a)
Oxidase positive
b)
Oxidase negative
c)
Delayed oxidase positive
d)
All of the above
13.
Which of the following medium is used to presumptively identify enterococci to presumptively identify enterococci and group D streptococci based on the ability of an organism to hydrolyze esculin?
a)
Indole Spot
b)
Bile esculin agar
c)
Gaby and Hadley reagents
d)
Hydrogen peroxide solution
14.
Which test is discussed in the following procedure? Step 1 - Inoculate one to two colonies from an 18- to 24-hour culture onto the surface of the slant. Step 2 - Incubate at 35°-37°C in ambient air for 48 hours. Step 3 - Observe for growth and blackening of the medium
a)
Indole test
b)
Coagulase test
c)
Bile esculin test
d)
Citrate test
15.
The following image shows the presence or absence of a ring. Which biochemical test is this?
a)
Coagulase test
b)
Catalase test
c)
Indole test
d)
Citrate test
16.
Which of the following media is used in the citrate test?
a)
Simmon’s citrate agar
b)
Bile esculin agar
c)
H202
d)
Both Band C
17.
A biochemical test was performed in a laboratory and color changes from green to blue. The slant was also observed. Which test is this?
a)
Negative Positive
b)
Coagulase test
c)
Indole test
d)
Citrate test
e)
Urease test
18.
Which of the following biochemical testis a popular diagnostic test for diagnosis of Helicobacter pylori?
a)
Coagulase test
b)
Urease test
c)
Citrate test
d)
Bile esculin test
19.
Which of the following is TRUE about the urease test? 1. Gastric endoscopy and biopsy are performed to collect stomach lining cells. These cells are placed into a medium containing urea.,
a)
1. Gastric endoscopy and biopsy are performed to collect stomach lining cells. These cells are placed into a medium containing urea.
b)
2. The urease produced by H. pylori hydrolyzes urea to ammonia and changes the color of the specimen from yellow to red.
c)
Both 1 & 2
20.
Which is a highly sensitive and specific test to detect Helicobacter pylori on the basis of urease activity?
a)
Rapid Urease Test
b)
Urea Breath Test
c)
Methyl red Test
d)
Both Aand C
21.
Which tube indicates a positive test for Methyl red test?
a)
Tube A
b)
Tube B
c)
Both A and B
d)
None of the above
22.
Which tube indicates a positive test for Voges—Proskauer (VP)?
a)
A
b)
B
c)
Both
d)
None
23.
What happens in negative staining? 1. Background is stained, 2. Microbes are unstained, 3. Background is unstained, 4. Microbes are stained
a)
1and 2
b)
2 and 3
c)
1,3and 4
d)
1and3
24.
Which of the following are not the use of negative staining?
a)
To study bacteria that are difficult to stain
b)
To stain delicate cells
c)
To view gram positive bacteria specially
d)
Electron microscopy
25.
Which of the following is the reagent of negative staining?
a)
Nigrosin
b)
Lesihaman stain
c)
Agro blue stain
d)
Congo red stain
26.
What type of angulation of tilting of the slide is required to spread the culture on slide in negative staining?
a)
Acute angle
b)
Obtuse angle
c)
Right angle
d)
Reflex angle
27.
For negative staining, how is the culture media is taken from the test tube containing culture?
a)
Inoculating loop
b)
Spatula
c)
Spoon
d)
All of the above
100 %
