NURSE-UN 75
Microbiology
Comprehensive Finals Review (Qns & Ans)
2025
1. Which of the following is the primary function of bacterial
flagella?
- A. Nutrient absorption
- B. DNA replication
- C. Motility
- D. Protein synthesis
- ANS: C. Motility
- Rationale: Bacterial flagella are primarily responsible for
the motility of the bacteria, allowing them to move towards
favorable environments.
©2024/2025
,2. What is the main component of the bacterial cell wall in
Gram-positive bacteria?
- A. Lipopolysaccharides
- B. Peptidoglycan
- C. Phospholipids
- D. Proteins
- ANS: B. Peptidoglycan
- Rationale: The cell wall of Gram-positive bacteria is mainly
composed of a thick layer of peptidoglycan, which provides
structural support and protection.
3. Which of the following viruses is known to cause the common
cold?
- A. Influenza virus
- B. Rhinovirus
- C. Hepatitis B virus
- D. Human immunodeficiency virus (HIV)
- ANS: B. Rhinovirus
- Rationale: Rhinovirus is the most common viral agent
responsible for causing the common cold.
©2024/2025
,4. Which of the following is a characteristic of prions?
- A. They contain DNA
- B. They are composed of proteins only
- C. They can be treated with antibiotics
- D. They have a lipid envelope
- ANS: B. They are composed of proteins only
- Rationale: Prions are infectious agents composed solely of
proteins and lack nucleic acids.
5. What is the primary mode of transmission for the Ebola virus?
- A. Airborne transmission
- B. Vector-borne transmission
- C. Direct contact with bodily fluids
- D. Contaminated food and water
- ANS: C. Direct contact with bodily fluids
- Rationale: The Ebola virus is primarily transmitted through
direct contact with the bodily fluids of infected individuals.
Fill-in-the-Blank Questions
6. The ________ is a structure that allows bacteria to adhere to
surfaces and form biofilms.
©2024/2025
, - ANS: pilus (or fimbria)
- Rationale: Pili (or fimbriae) are hair-like structures on the
surface of bacteria that facilitate adhesion to surfaces and biofilm
formation.
7. ________ is the process by which bacteria exchange genetic
material through direct contact.
- ANS: Conjugation
- Rationale: Conjugation is a mechanism of horizontal gene
transfer in bacteria involving direct cell-to-cell contact.
8. The ________ cycle is the process by which a virus replicates
within a host cell and eventually causes the cell to burst.
- ANS: lytic
- Rationale: The lytic cycle involves the replication of a virus
within a host cell, leading to cell lysis and the release of new viral
particles.
9. ________ is the enzyme responsible for synthesizing DNA
from an RNA template in retroviruses.
- ANS: Reverse transcriptase
- Rationale: Reverse transcriptase is an enzyme used by
retroviruses to convert their RNA genome into DNA.
©2024/2025
Microbiology
Comprehensive Finals Review (Qns & Ans)
2025
1. Which of the following is the primary function of bacterial
flagella?
- A. Nutrient absorption
- B. DNA replication
- C. Motility
- D. Protein synthesis
- ANS: C. Motility
- Rationale: Bacterial flagella are primarily responsible for
the motility of the bacteria, allowing them to move towards
favorable environments.
©2024/2025
,2. What is the main component of the bacterial cell wall in
Gram-positive bacteria?
- A. Lipopolysaccharides
- B. Peptidoglycan
- C. Phospholipids
- D. Proteins
- ANS: B. Peptidoglycan
- Rationale: The cell wall of Gram-positive bacteria is mainly
composed of a thick layer of peptidoglycan, which provides
structural support and protection.
3. Which of the following viruses is known to cause the common
cold?
- A. Influenza virus
- B. Rhinovirus
- C. Hepatitis B virus
- D. Human immunodeficiency virus (HIV)
- ANS: B. Rhinovirus
- Rationale: Rhinovirus is the most common viral agent
responsible for causing the common cold.
©2024/2025
,4. Which of the following is a characteristic of prions?
- A. They contain DNA
- B. They are composed of proteins only
- C. They can be treated with antibiotics
- D. They have a lipid envelope
- ANS: B. They are composed of proteins only
- Rationale: Prions are infectious agents composed solely of
proteins and lack nucleic acids.
5. What is the primary mode of transmission for the Ebola virus?
- A. Airborne transmission
- B. Vector-borne transmission
- C. Direct contact with bodily fluids
- D. Contaminated food and water
- ANS: C. Direct contact with bodily fluids
- Rationale: The Ebola virus is primarily transmitted through
direct contact with the bodily fluids of infected individuals.
Fill-in-the-Blank Questions
6. The ________ is a structure that allows bacteria to adhere to
surfaces and form biofilms.
©2024/2025
, - ANS: pilus (or fimbria)
- Rationale: Pili (or fimbriae) are hair-like structures on the
surface of bacteria that facilitate adhesion to surfaces and biofilm
formation.
7. ________ is the process by which bacteria exchange genetic
material through direct contact.
- ANS: Conjugation
- Rationale: Conjugation is a mechanism of horizontal gene
transfer in bacteria involving direct cell-to-cell contact.
8. The ________ cycle is the process by which a virus replicates
within a host cell and eventually causes the cell to burst.
- ANS: lytic
- Rationale: The lytic cycle involves the replication of a virus
within a host cell, leading to cell lysis and the release of new viral
particles.
9. ________ is the enzyme responsible for synthesizing DNA
from an RNA template in retroviruses.
- ANS: Reverse transcriptase
- Rationale: Reverse transcriptase is an enzyme used by
retroviruses to convert their RNA genome into DNA.
©2024/2025
