Microbiology for Nurses 2026 Practice Test
Questions Detailed Explanations Microorganisms
Infectious Diseases Transmission Immunity
Infection Control Clinical Review
SECTION 1: MICROORGANISMS (Questions 1-32)
1. A nurse is reviewing the classification of microorganisms. Which of the
following is a prokaryotic organism?
A) Fungi
B) Bacteria
C) Protozoa
D) Helminths
Rationale: Bacteria are prokaryotic organisms, meaning they lack a true nucleus
and membrane-bound organelles. Fungi, protozoa, and helminths are eukaryotic,
possessing a true nucleus and membrane-bound organelles. This distinction is
important for understanding antibiotic mechanisms, as antibiotics target
prokaryotic structures.
2. A nurse is teaching about viruses. Which statement is correct?
A) Viruses are prokaryotic cells.
B) Viruses require a host cell to replicate.
C) Viruses are susceptible to antibiotics.
D) Viruses contain both DNA and RNA simultaneously.
Rationale: Viruses are obligate intracellular parasites that require a host cell to
replicate. They are not cells, lack metabolic machinery, and are not susceptible to
antibiotics. Most viruses contain either DNA or RNA, not both.
,3. A client is diagnosed with a fungal infection. Which class of microorganisms
is responsible?
A) Bacteria
B) Viruses
C) Fungi
D) Protozoa
Rationale: Fungi are eukaryotic microorganisms that include yeasts and molds.
They cause infections such as candidiasis, aspergillosis, and dermatophytosis.
Treatment requires antifungal medications, as antibiotics are ineffective against
fungi.
4. A nurse is reviewing the structure of bacteria. Which component is
responsible for motility?
A) Pili
B) Capsule
C) Flagella
D) Cell wall
Rationale: Flagella are whip-like appendages that provide motility to bacteria. Pili
are involved in attachment and conjugation. The capsule protects against
phagocytosis. The cell wall provides structural support and is the target of many
antibiotics.
5. A client is diagnosed with malaria. Which type of microorganism causes
this disease?
A) Bacteria
B) Virus
C) Fungus
D) Protozoa
,Rationale: Malaria is caused by Plasmodium species, which are protozoa.
Protozoa are single-celled eukaryotic organisms. Malaria is transmitted by the
Anopheles mosquito and causes cyclic fever, chills, and anemia.
6. A nurse is teaching about bacterial shapes. Which term describes spherical
bacteria?
A) Bacilli
B) Cocci
C) Spirilla
D) Vibrio
Rationale: Cocci are spherical bacteria (e.g., Staphylococcus, Streptococcus).
Bacilli are rod-shaped. Spirilla are spiral-shaped. Vibrio are comma-shaped.
Bacterial shape is important for identification and classification.
7. A client is diagnosed with tuberculosis. Which type of microorganism
causes this disease?
A) Virus
B) Fungus
C) Bacterium
D) Protozoan
Rationale: Tuberculosis is caused by Mycobacterium tuberculosis, an acid-fast
bacillus. It primarily affects the lungs but can disseminate. Treatment requires
long-term multidrug therapy due to the organism's slow growth and resistance.
8. A nurse is reviewing the structure of viruses. Which component is the outer
protein coat called?
, A) Capsule
B) Envelope
C) Capsid
D) Nucleoid
Rationale: The capsid is the outer protein coat of a virus that protects the genetic
material. Some viruses also have an envelope derived from the host cell
membrane. The capsid is important for viral attachment and entry into host cells.
9. A client is diagnosed with candidiasis. Which type of microorganism causes
this infection?
A) Bacteria
B) Virus
C) Fungus
D) Protozoan
Rationale: Candidiasis is caused by Candida species, which are yeasts (fungi). It
commonly affects the mouth, esophagus, and genital tract. Risk factors include
antibiotic use, immunosuppression, and diabetes. Treatment is with antifungals.
10. A nurse is teaching about prions. Which statement is correct?
A) Prions are bacteria.
B) Prions are infectious proteins.
C) Prions contain DNA.
D) Prions are easily destroyed by standard sterilization.
Rationale: Prions are infectious proteins that lack nucleic acids (DNA/RNA).
They cause neurodegenerative diseases such as Creutzfeldt-Jakob disease. Prions
are resistant to standard sterilization methods and require special decontamination
procedures.
Questions Detailed Explanations Microorganisms
Infectious Diseases Transmission Immunity
Infection Control Clinical Review
SECTION 1: MICROORGANISMS (Questions 1-32)
1. A nurse is reviewing the classification of microorganisms. Which of the
following is a prokaryotic organism?
A) Fungi
B) Bacteria
C) Protozoa
D) Helminths
Rationale: Bacteria are prokaryotic organisms, meaning they lack a true nucleus
and membrane-bound organelles. Fungi, protozoa, and helminths are eukaryotic,
possessing a true nucleus and membrane-bound organelles. This distinction is
important for understanding antibiotic mechanisms, as antibiotics target
prokaryotic structures.
2. A nurse is teaching about viruses. Which statement is correct?
A) Viruses are prokaryotic cells.
B) Viruses require a host cell to replicate.
C) Viruses are susceptible to antibiotics.
D) Viruses contain both DNA and RNA simultaneously.
Rationale: Viruses are obligate intracellular parasites that require a host cell to
replicate. They are not cells, lack metabolic machinery, and are not susceptible to
antibiotics. Most viruses contain either DNA or RNA, not both.
,3. A client is diagnosed with a fungal infection. Which class of microorganisms
is responsible?
A) Bacteria
B) Viruses
C) Fungi
D) Protozoa
Rationale: Fungi are eukaryotic microorganisms that include yeasts and molds.
They cause infections such as candidiasis, aspergillosis, and dermatophytosis.
Treatment requires antifungal medications, as antibiotics are ineffective against
fungi.
4. A nurse is reviewing the structure of bacteria. Which component is
responsible for motility?
A) Pili
B) Capsule
C) Flagella
D) Cell wall
Rationale: Flagella are whip-like appendages that provide motility to bacteria. Pili
are involved in attachment and conjugation. The capsule protects against
phagocytosis. The cell wall provides structural support and is the target of many
antibiotics.
5. A client is diagnosed with malaria. Which type of microorganism causes
this disease?
A) Bacteria
B) Virus
C) Fungus
D) Protozoa
,Rationale: Malaria is caused by Plasmodium species, which are protozoa.
Protozoa are single-celled eukaryotic organisms. Malaria is transmitted by the
Anopheles mosquito and causes cyclic fever, chills, and anemia.
6. A nurse is teaching about bacterial shapes. Which term describes spherical
bacteria?
A) Bacilli
B) Cocci
C) Spirilla
D) Vibrio
Rationale: Cocci are spherical bacteria (e.g., Staphylococcus, Streptococcus).
Bacilli are rod-shaped. Spirilla are spiral-shaped. Vibrio are comma-shaped.
Bacterial shape is important for identification and classification.
7. A client is diagnosed with tuberculosis. Which type of microorganism
causes this disease?
A) Virus
B) Fungus
C) Bacterium
D) Protozoan
Rationale: Tuberculosis is caused by Mycobacterium tuberculosis, an acid-fast
bacillus. It primarily affects the lungs but can disseminate. Treatment requires
long-term multidrug therapy due to the organism's slow growth and resistance.
8. A nurse is reviewing the structure of viruses. Which component is the outer
protein coat called?
, A) Capsule
B) Envelope
C) Capsid
D) Nucleoid
Rationale: The capsid is the outer protein coat of a virus that protects the genetic
material. Some viruses also have an envelope derived from the host cell
membrane. The capsid is important for viral attachment and entry into host cells.
9. A client is diagnosed with candidiasis. Which type of microorganism causes
this infection?
A) Bacteria
B) Virus
C) Fungus
D) Protozoan
Rationale: Candidiasis is caused by Candida species, which are yeasts (fungi). It
commonly affects the mouth, esophagus, and genital tract. Risk factors include
antibiotic use, immunosuppression, and diabetes. Treatment is with antifungals.
10. A nurse is teaching about prions. Which statement is correct?
A) Prions are bacteria.
B) Prions are infectious proteins.
C) Prions contain DNA.
D) Prions are easily destroyed by standard sterilization.
Rationale: Prions are infectious proteins that lack nucleic acids (DNA/RNA).
They cause neurodegenerative diseases such as Creutzfeldt-Jakob disease. Prions
are resistant to standard sterilization methods and require special decontamination
procedures.
