BIOS 242 Microbiology with Lab Exam
2 (Latest Update ) Anatomy
and Physiology IV with Lab | Questions
& Answers | 100% Correct | Grade A -
Chamberlain
1. What is the main function of the bacterial capsule?
A. Protein synthesis
B. DNA replication
C. Protection against phagocytosis
D. Motility
Correct Answer: C. Protection against phagocytosis
Rationale: Capsules prevent immune cells from engulfing bacteria,
enhancing virulence.
2. Which bacterial genus is known for forming endospores?
A. Staphylococcus
B. Bacillus
C. Escherichia
D. Salmonella
Correct Answer: B. Bacillus
Rationale: Bacillus species produce endospores to survive harsh
conditions.
3. Which of the following is a Gram-positive bacterium?
A. Escherichia coli
B. Staphylococcus aureus
C. Salmonella enterica
D. Neisseria gonorrhoeae
Correct Answer: B. Staphylococcus aureus
,Rationale: S. aureus retains crystal violet dye, appearing purple
under Gram stain.
4. Which Gram-negative bacterium is a common cause of urinary
tract infections?
A. Bacillus subtilis
B. Escherichia coli
C. Staphylococcus epidermidis
D. Clostridium tetani
Correct Answer: B. Escherichia coli
Rationale: E. coli is a leading cause of UTIs due to its ability to
colonize the urinary tract.
5. Which term describes bacteria that can grow with or without
oxygen?
A. Obligate anaerobe
B. Obligate aerobe
C. Facultative anaerobe
D. Microaerophile
Correct Answer: C. Facultative anaerobe
Rationale: Facultative anaerobes can switch between aerobic and
anaerobic metabolism.
6. Which type of microbial metabolism produces lactic acid from
glucose?
A. Alcoholic fermentation
B. Lactic acid fermentation
C. Aerobic respiration
D. Photosynthesis
Correct Answer: B. Lactic acid fermentation
Rationale: Lactic acid fermentation converts glucose into lactic acid
under anaerobic conditions.
7. What is the main function of bacterial flagella?
, A. DNA replication
B. Motility
C. Attachment to surfaces
D. Protein synthesis
Correct Answer: B. Motility
Rationale: Flagella propel bacteria, allowing them to move toward
favorable environments.
8. Which bacterial arrangement is characterized by chains of
spherical cells?
A. Staphylococci
B. Streptococci
C. Diplococci
D. Tetrads
Correct Answer: B. Streptococci
Rationale: Streptococci divide in one plane forming chains.
9. Which staining technique is used to detect acid-fast bacteria?
A. Gram stain
B. Simple stain
C. Acid-fast stain (Ziehl-Neelsen)
D. Capsule stain
Correct Answer: C. Acid-fast stain (Ziehl-Neelsen)
Rationale: Acid-fast bacteria resist Gram stain due to their waxy
mycolic acid cell walls.
10. Which of the following microbes is a eukaryote?
A. Escherichia coli
B. Bacillus subtilis
C. Candida albicans
D. Staphylococcus aureus
Correct Answer: C. Candida albicans
Rationale: Fungi like Candida are eukaryotic organisms with
membrane-bound organelles.
2 (Latest Update ) Anatomy
and Physiology IV with Lab | Questions
& Answers | 100% Correct | Grade A -
Chamberlain
1. What is the main function of the bacterial capsule?
A. Protein synthesis
B. DNA replication
C. Protection against phagocytosis
D. Motility
Correct Answer: C. Protection against phagocytosis
Rationale: Capsules prevent immune cells from engulfing bacteria,
enhancing virulence.
2. Which bacterial genus is known for forming endospores?
A. Staphylococcus
B. Bacillus
C. Escherichia
D. Salmonella
Correct Answer: B. Bacillus
Rationale: Bacillus species produce endospores to survive harsh
conditions.
3. Which of the following is a Gram-positive bacterium?
A. Escherichia coli
B. Staphylococcus aureus
C. Salmonella enterica
D. Neisseria gonorrhoeae
Correct Answer: B. Staphylococcus aureus
,Rationale: S. aureus retains crystal violet dye, appearing purple
under Gram stain.
4. Which Gram-negative bacterium is a common cause of urinary
tract infections?
A. Bacillus subtilis
B. Escherichia coli
C. Staphylococcus epidermidis
D. Clostridium tetani
Correct Answer: B. Escherichia coli
Rationale: E. coli is a leading cause of UTIs due to its ability to
colonize the urinary tract.
5. Which term describes bacteria that can grow with or without
oxygen?
A. Obligate anaerobe
B. Obligate aerobe
C. Facultative anaerobe
D. Microaerophile
Correct Answer: C. Facultative anaerobe
Rationale: Facultative anaerobes can switch between aerobic and
anaerobic metabolism.
6. Which type of microbial metabolism produces lactic acid from
glucose?
A. Alcoholic fermentation
B. Lactic acid fermentation
C. Aerobic respiration
D. Photosynthesis
Correct Answer: B. Lactic acid fermentation
Rationale: Lactic acid fermentation converts glucose into lactic acid
under anaerobic conditions.
7. What is the main function of bacterial flagella?
, A. DNA replication
B. Motility
C. Attachment to surfaces
D. Protein synthesis
Correct Answer: B. Motility
Rationale: Flagella propel bacteria, allowing them to move toward
favorable environments.
8. Which bacterial arrangement is characterized by chains of
spherical cells?
A. Staphylococci
B. Streptococci
C. Diplococci
D. Tetrads
Correct Answer: B. Streptococci
Rationale: Streptococci divide in one plane forming chains.
9. Which staining technique is used to detect acid-fast bacteria?
A. Gram stain
B. Simple stain
C. Acid-fast stain (Ziehl-Neelsen)
D. Capsule stain
Correct Answer: C. Acid-fast stain (Ziehl-Neelsen)
Rationale: Acid-fast bacteria resist Gram stain due to their waxy
mycolic acid cell walls.
10. Which of the following microbes is a eukaryote?
A. Escherichia coli
B. Bacillus subtilis
C. Candida albicans
D. Staphylococcus aureus
Correct Answer: C. Candida albicans
Rationale: Fungi like Candida are eukaryotic organisms with
membrane-bound organelles.
