BIOD 171 Microbiology Lab Notebook for Labs
1–9 (Latest) Portage Learning
Lab 1: Basics of a Microbiology Laboratory
1. What is the primary purpose of a Bunsen burner in a microbiology lab?
A) To sterilize media
B) To heat liquids
C) To create an updraft and prevent contamination of cultures
D) To provide a sterile work area
✓ C) To create an updraft and prevent contamination of cultures
2. What are the four main vital signs for lab safety described by the acronym P.A.S.S.?
A) Pull, Aim, Squeeze, Sweep
B) Point, Alert, Spray, Stop
C) Prevent, Assess, Secure, Shut
✓ A) Pull, Aim, Squeeze, Sweep
3. What type of fire extinguisher is used for common combustibles like paper or wood?
A) Class A
B) Class B
C) Class C
D) Class D
✓ A) Class A
4. What is the purpose of an eyewash station?
A) To rinse off chemical spills on skin
B) To flush the eyes in case of chemical or contaminant exposure
C) To provide sterile water for experiments
✓ B) To flush the eyes in case of chemical or contaminant exposure
5. Proper hand washing in a lab should last for at least how long?
A) 5 seconds
B) 20 seconds
C) 1 minute
D) 2 minutes
✓ B) 20 seconds
Lab 2: Microscopy
, 6. What is the total magnification when using the 100x objective lens?
A) 100x
B) 400x
C) 1000x
D) 2000x
✓ C) 1000x (10x ocular * 100x objective)
7. What is the name of the microscope part that controls the amount of light reaching
the specimen?
A) Diaphragm
B) Condenser
C) Ocular
D) Coarse Focus
✓ A) Diaphragm
8. Why is immersion oil used with the 100x objective lens?
A) To protect the lens
B) To reduce light scattering and increase resolution
C) To sterilize the slide
D) To stain the specimen
✓ B) To reduce light scattering and increase resolution
9. Which objective lens should you always start with when focusing on a specimen?
A) 4x (Scanning)
B) 10x (Low Power)
C) 40x (High Power)
D) 100x (Oil Immersion)
✓ A) 4x (Scanning)
10. Parfocal is a microscope feature that means:
A) The light intensity is constant.
B) The specimen remains in focus when switching between objective lenses.
C) The microscope has two ocular lenses.
✓ B) The specimen remains in focus when switching between objective lenses.
Lab 3: Aseptic Technique and Bacterial Cultivation
11. What is the primary goal of aseptic technique?
A) To grow bacteria quickly
B) To prevent contamination of pure cultures and the environment
, C) To make media plates
D) To identify unknown bacteria
✓ B) To prevent contamination of pure cultures and the environment
12. Before and after transferring bacteria, the inoculating loop should be:
A) Rinsed with water
B) Wiped with a paper towel
C) Sterilized by flaming until red-hot
D) Dipped in ethanol
✓ C) Sterilized by flaming until red-hot
13. What is the term for a culture containing only a single type of microbe?
A) Mixed culture
B) Contaminated culture
C) Pure culture
D) Stock culture
✓ C) Pure culture
14. A TSA (Trypticase Soy Agar) slant is best used for what purpose?
A) Long-term storage of bacteria
B) Observing colony morphology
C) Performing gram stains
D) Creating bacterial lawns
✓ A) Long-term storage of bacteria
15. When incubating plates, why are they placed upside down (inverted)?
A) To save space
B) To prevent condensation from dripping onto the culture surface
C) To make them easier to label
D) To slow bacterial growth
✓ B) To prevent condensation from dripping onto the culture surface
Lab 4: Bacterial Staining
16. What is the purpose of heat fixation during smear preparation?
A) To stain the cells
B) To kill the bacteria and adhere them to the slide
C) To make the cells more visible
D) To sterilize the slide
✓ B) To kill the bacteria and adhere them to the slide
, 17. The primary stain in the Gram stain procedure is:
A) Iodine
B) Safranin
C) Crystal Violet
D) Ethanol
✓ C) Crystal Violet
18. What is the mordant in the Gram stain?
A) Crystal Violet
B) Safranin
C) Iodine
D) Decolorizer
✓ C) Iodine
19. Gram-negative bacteria appear what color after a correct Gram stain?
A) Purple
B) Pink/Red
C) Colorless
D) Green
✓ B) Pink/Red
20. The critical step in the Gram stain that differentiates between Gram-positive and
Gram-negative cells is:
A) Application of the primary stain
B) Application of the mordant
C) The decolorization step
D) Application of the counterstain
✓ C) The decolorization step
21. What staining technique is used to identify bacteria with mycolic acid in their cell
walls, like Myobacterium tuberculosis?
A) Gram Stain
B) Capsule Stain
C) Endospore Stain
D) Acid-Fast Stain
✓ D) Acid-Fast Stain
22. In the Acid-Fast stain, acid-fast cells retain the primary stain and appear what color?
A) Blue
B) Green
1–9 (Latest) Portage Learning
Lab 1: Basics of a Microbiology Laboratory
1. What is the primary purpose of a Bunsen burner in a microbiology lab?
A) To sterilize media
B) To heat liquids
C) To create an updraft and prevent contamination of cultures
D) To provide a sterile work area
✓ C) To create an updraft and prevent contamination of cultures
2. What are the four main vital signs for lab safety described by the acronym P.A.S.S.?
A) Pull, Aim, Squeeze, Sweep
B) Point, Alert, Spray, Stop
C) Prevent, Assess, Secure, Shut
✓ A) Pull, Aim, Squeeze, Sweep
3. What type of fire extinguisher is used for common combustibles like paper or wood?
A) Class A
B) Class B
C) Class C
D) Class D
✓ A) Class A
4. What is the purpose of an eyewash station?
A) To rinse off chemical spills on skin
B) To flush the eyes in case of chemical or contaminant exposure
C) To provide sterile water for experiments
✓ B) To flush the eyes in case of chemical or contaminant exposure
5. Proper hand washing in a lab should last for at least how long?
A) 5 seconds
B) 20 seconds
C) 1 minute
D) 2 minutes
✓ B) 20 seconds
Lab 2: Microscopy
, 6. What is the total magnification when using the 100x objective lens?
A) 100x
B) 400x
C) 1000x
D) 2000x
✓ C) 1000x (10x ocular * 100x objective)
7. What is the name of the microscope part that controls the amount of light reaching
the specimen?
A) Diaphragm
B) Condenser
C) Ocular
D) Coarse Focus
✓ A) Diaphragm
8. Why is immersion oil used with the 100x objective lens?
A) To protect the lens
B) To reduce light scattering and increase resolution
C) To sterilize the slide
D) To stain the specimen
✓ B) To reduce light scattering and increase resolution
9. Which objective lens should you always start with when focusing on a specimen?
A) 4x (Scanning)
B) 10x (Low Power)
C) 40x (High Power)
D) 100x (Oil Immersion)
✓ A) 4x (Scanning)
10. Parfocal is a microscope feature that means:
A) The light intensity is constant.
B) The specimen remains in focus when switching between objective lenses.
C) The microscope has two ocular lenses.
✓ B) The specimen remains in focus when switching between objective lenses.
Lab 3: Aseptic Technique and Bacterial Cultivation
11. What is the primary goal of aseptic technique?
A) To grow bacteria quickly
B) To prevent contamination of pure cultures and the environment
, C) To make media plates
D) To identify unknown bacteria
✓ B) To prevent contamination of pure cultures and the environment
12. Before and after transferring bacteria, the inoculating loop should be:
A) Rinsed with water
B) Wiped with a paper towel
C) Sterilized by flaming until red-hot
D) Dipped in ethanol
✓ C) Sterilized by flaming until red-hot
13. What is the term for a culture containing only a single type of microbe?
A) Mixed culture
B) Contaminated culture
C) Pure culture
D) Stock culture
✓ C) Pure culture
14. A TSA (Trypticase Soy Agar) slant is best used for what purpose?
A) Long-term storage of bacteria
B) Observing colony morphology
C) Performing gram stains
D) Creating bacterial lawns
✓ A) Long-term storage of bacteria
15. When incubating plates, why are they placed upside down (inverted)?
A) To save space
B) To prevent condensation from dripping onto the culture surface
C) To make them easier to label
D) To slow bacterial growth
✓ B) To prevent condensation from dripping onto the culture surface
Lab 4: Bacterial Staining
16. What is the purpose of heat fixation during smear preparation?
A) To stain the cells
B) To kill the bacteria and adhere them to the slide
C) To make the cells more visible
D) To sterilize the slide
✓ B) To kill the bacteria and adhere them to the slide
, 17. The primary stain in the Gram stain procedure is:
A) Iodine
B) Safranin
C) Crystal Violet
D) Ethanol
✓ C) Crystal Violet
18. What is the mordant in the Gram stain?
A) Crystal Violet
B) Safranin
C) Iodine
D) Decolorizer
✓ C) Iodine
19. Gram-negative bacteria appear what color after a correct Gram stain?
A) Purple
B) Pink/Red
C) Colorless
D) Green
✓ B) Pink/Red
20. The critical step in the Gram stain that differentiates between Gram-positive and
Gram-negative cells is:
A) Application of the primary stain
B) Application of the mordant
C) The decolorization step
D) Application of the counterstain
✓ C) The decolorization step
21. What staining technique is used to identify bacteria with mycolic acid in their cell
walls, like Myobacterium tuberculosis?
A) Gram Stain
B) Capsule Stain
C) Endospore Stain
D) Acid-Fast Stain
✓ D) Acid-Fast Stain
22. In the Acid-Fast stain, acid-fast cells retain the primary stain and appear what color?
A) Blue
B) Green
