BIOD171
Essential Microbiology
FINAL EXAM GUIDE
© Portage 2024/2025
, 1. Which of the following statements correctly describes biofilms?
A) They are unicellular organisms.
B) They consist of aggregated cells encased in a matrix.
C) They are exclusively composed of prokaryotic cells.
D) They are always harmful to the host.
Answer: B
Rationale: Biofilms are communities of microorganisms that
attach to surfaces and are embedded in a self-produced matrix,
allowing for enhanced survival and resistance to antibiotics.
---
2. The scenario analysis of a new vaccine design against a bacterial
pathogen relies heavily on which of the following immune
responses?
A) Innate immunity
B) Humoral immunity
C) Cell-mediated immunity
D) Both humoral and cell-mediated immunity
Answer: D
© Portage 2024/2025
, Rationale: Effective vaccines elicit both humoral (antibody
production) and cell-mediated immune responses for stronger,
longer-lasting immunity.
---
3. In a laboratory experiment, a bacterium is observed producing
toxin only in the presence of a specific host tissue. This is an
example of:
A) Commensalism
B) Opportunistic infection
C) Pathogenicity
D) Symbiosis
Answer: C
Rationale: Pathogenicity refers to the ability of an organism to
cause disease, often requiring specific interactions with host tissues.
---
4. You are studying the effect of ultraviolet light on microbial
DNA. Which mechanism primarily repairs UV-induced DNA
damage in bacteria?
A) Photoreactivation
© Portage 2024/2025
Essential Microbiology
FINAL EXAM GUIDE
© Portage 2024/2025
, 1. Which of the following statements correctly describes biofilms?
A) They are unicellular organisms.
B) They consist of aggregated cells encased in a matrix.
C) They are exclusively composed of prokaryotic cells.
D) They are always harmful to the host.
Answer: B
Rationale: Biofilms are communities of microorganisms that
attach to surfaces and are embedded in a self-produced matrix,
allowing for enhanced survival and resistance to antibiotics.
---
2. The scenario analysis of a new vaccine design against a bacterial
pathogen relies heavily on which of the following immune
responses?
A) Innate immunity
B) Humoral immunity
C) Cell-mediated immunity
D) Both humoral and cell-mediated immunity
Answer: D
© Portage 2024/2025
, Rationale: Effective vaccines elicit both humoral (antibody
production) and cell-mediated immune responses for stronger,
longer-lasting immunity.
---
3. In a laboratory experiment, a bacterium is observed producing
toxin only in the presence of a specific host tissue. This is an
example of:
A) Commensalism
B) Opportunistic infection
C) Pathogenicity
D) Symbiosis
Answer: C
Rationale: Pathogenicity refers to the ability of an organism to
cause disease, often requiring specific interactions with host tissues.
---
4. You are studying the effect of ultraviolet light on microbial
DNA. Which mechanism primarily repairs UV-induced DNA
damage in bacteria?
A) Photoreactivation
© Portage 2024/2025
