MICROBIOLOGY EXAM 1 PRACTICE
TEST QUESTIONS AND ANSWERS WITH
COMPLETE SOLUTIONS ALREADY
PASSED LATEST UPDATED 2026
Which bacterial cellular structure frequently carries non-essential genes that
encode for enzymes and antibiotic resistance?
✔✔ Plasmid
(Plasmids are extrachromosomal circular DNA molecules that can replicate
independently and often confer selective advantages like antibiotic resistance or
virulence factors).
What is considered the most important bacterial structure responsible for
mediating adherence and attachment to host cells and surfaces?
✔✔ Glycocalyx (including capsules and slime layers)
(The sticky extracellular polymeric matrix allows bacteria to adhere firmly to
tissues and medical devices, forming biofilms).
Which of the following organisms is NOT a Gram-negative bacterium
(Clostridium perfringens, Vibrio cholerae, Escherichia coli, Bordetella
pertussis)?
✔✔ Clostridium perfringens
(Clostridium perfringens is a Gram-positive, spore-forming, anaerobic rod. The
other three—Vibrio cholerae, E. coli, and Bordetella pertussis—are Gram-
negative bacilli)
4. Which of the following is not true related to endotoxins?
Endotoxins are secreted from cells.
Can be linked to Meningococcemia
Produced by gram negative microorganisms
Can cause fever -ANSWER✔✔Endotoxins are secreted from cells.
, 5. Which of the following microorganisms stain well?
Escherichia coli
Legionella pneumophila
Treponema
Chlamydia -ANSWER✔✔Escherichia coli
6. Which of the following microorganisms are not matched correctly with the
appropriate isolation media?
Fungi - Sabourand's agar
Neisseria gonorrhoeae - Pink colonies media
Haemophilus influenzae - Chocolate agar
Mycobacterium tuberculosis - Lowenstein-Jensen agar -ANSWER✔✔Neisseria
gonorrhoeae - Pink colonies media
7. Which of the following diseases and bacteria are matched up incorrectly?
Cellulitis - Pasteurella multocida
Tularemia - Francisella tularensis
Gastritis - Heliobacter pylori
Lyme disease - Yersinia pestis -ANSWER✔✔Lyme disease - Yersinia pestis
8. Which of the following diseases and bacteria are matched up incorrectly?
Treponema pallidum - Syphilis
Tinea nigra - Cladosporium werneckii
Borrelia burgdorferi - Lyme disease
TEST QUESTIONS AND ANSWERS WITH
COMPLETE SOLUTIONS ALREADY
PASSED LATEST UPDATED 2026
Which bacterial cellular structure frequently carries non-essential genes that
encode for enzymes and antibiotic resistance?
✔✔ Plasmid
(Plasmids are extrachromosomal circular DNA molecules that can replicate
independently and often confer selective advantages like antibiotic resistance or
virulence factors).
What is considered the most important bacterial structure responsible for
mediating adherence and attachment to host cells and surfaces?
✔✔ Glycocalyx (including capsules and slime layers)
(The sticky extracellular polymeric matrix allows bacteria to adhere firmly to
tissues and medical devices, forming biofilms).
Which of the following organisms is NOT a Gram-negative bacterium
(Clostridium perfringens, Vibrio cholerae, Escherichia coli, Bordetella
pertussis)?
✔✔ Clostridium perfringens
(Clostridium perfringens is a Gram-positive, spore-forming, anaerobic rod. The
other three—Vibrio cholerae, E. coli, and Bordetella pertussis—are Gram-
negative bacilli)
4. Which of the following is not true related to endotoxins?
Endotoxins are secreted from cells.
Can be linked to Meningococcemia
Produced by gram negative microorganisms
Can cause fever -ANSWER✔✔Endotoxins are secreted from cells.
, 5. Which of the following microorganisms stain well?
Escherichia coli
Legionella pneumophila
Treponema
Chlamydia -ANSWER✔✔Escherichia coli
6. Which of the following microorganisms are not matched correctly with the
appropriate isolation media?
Fungi - Sabourand's agar
Neisseria gonorrhoeae - Pink colonies media
Haemophilus influenzae - Chocolate agar
Mycobacterium tuberculosis - Lowenstein-Jensen agar -ANSWER✔✔Neisseria
gonorrhoeae - Pink colonies media
7. Which of the following diseases and bacteria are matched up incorrectly?
Cellulitis - Pasteurella multocida
Tularemia - Francisella tularensis
Gastritis - Heliobacter pylori
Lyme disease - Yersinia pestis -ANSWER✔✔Lyme disease - Yersinia pestis
8. Which of the following diseases and bacteria are matched up incorrectly?
Treponema pallidum - Syphilis
Tinea nigra - Cladosporium werneckii
Borrelia burgdorferi - Lyme disease
