2026 Microbiology for Nursing Study
Guide Exam Prep Microorganisms •
Bacteria • Viruses • Fungi • Parasites •
Infection Control • Clinical
Applications Review
SECTION I: INTRODUCTION TO MICROBIOLOGY &
MICROORGANISM CLASSIFICATION (Questions 1–25)
1. A nurse is reviewing the characteristics of microorganisms. Which
statement best describes prokaryotes?
A. They have a true nucleus and membrane-bound organelles
B. They lack a true nucleus and membrane-bound organelles
C. They are larger than eukaryotic cells
D. They reproduce only sexually
Rationale: Prokaryotes (bacteria) lack a true nucleus and membrane-bound
organelles. Their genetic material is contained in a single circular chromosome in
the nucleoid region. Eukaryotes (fungi, protozoa, helminths) have a true nucleus
and membrane-bound organelles.
2. A nurse is teaching a student about the classification of microorganisms.
Which microorganism is classified as a prokaryote?
A. Fungi
B. Protozoa
C. Bacteria
D. Helminths
,Rationale: Bacteria are prokaryotes, meaning they lack a true nucleus and
membrane-bound organelles. Fungi, protozoa, and helminths are eukaryotes.
3. A nurse is reviewing the characteristics of viruses. Which statement best
describes viruses?
A. They are living cells that can reproduce independently
B. They are obligate intracellular parasites that require a host cell to replicate
C. They contain both DNA and RNA simultaneously
D. They are larger than bacteria
Rationale: Viruses are obligate intracellular parasites that require a host cell to
replicate. They contain either DNA or RNA, not both, and are much smaller than
bacteria.
4. A nurse is teaching about the classification of microorganisms. Which
microorganism is classified as a eukaryote?
A. Bacteria
B. Fungi
C. Viruses
D. Prions
Rationale: Fungi are eukaryotes, meaning they have a true nucleus and
membrane-bound organelles. Bacteria are prokaryotes, viruses are acellular, and
prions are infectious proteins.
5. A nurse is reviewing the structure of bacteria. Which structure is
responsible for bacterial motility?
A. Pili
B. Capsule
,C. Flagella
D. Cell wall
Rationale: Flagella are long, whip-like appendages that provide motility for
bacteria. Pili are involved in attachment and conjugation, the capsule provides
protection, and the cell wall provides structural support.
6. A nurse is reviewing the structure of bacteria. Which structure helps
bacteria adhere to surfaces and resist phagocytosis?
A. Flagella
B. Capsule
C. Ribosomes
D. Nucleoid
Rationale: The capsule is a polysaccharide layer outside the cell wall that helps
bacteria adhere to surfaces and resist phagocytosis by host immune cells.
7. A nurse is reviewing the structure of bacteria. Which structure is involved
in horizontal gene transfer between bacteria?
A. Flagella
B. Capsule
C. Pili
D. Cell membrane
Rationale: Pili (sex pili) are involved in conjugation, a form of horizontal gene
transfer where genetic material is transferred between bacteria.
8. A nurse is reviewing the classification of bacteria by shape. Which term
describes spherical bacteria?
, A. Bacilli
B. Cocci
C. Spirilla
D. Vibrios
Rationale: Cocci are spherical bacteria. Bacilli are rod-shaped, spirilla are spiral-
shaped, and vibrios are comma-shaped.
9. A nurse is reviewing the classification of bacteria by shape. Which term
describes rod-shaped bacteria?
A. Cocci
B. Bacilli
C. Spirilla
D. Spirochetes
Rationale: Bacilli are rod-shaped bacteria. Cocci are spherical, spirilla are spiral-
shaped, and spirochetes are flexible spiral-shaped bacteria.
10. A nurse is reviewing the classification of bacteria by Gram stain. Which
color indicates Gram-positive bacteria?
A. Red/pink
B. Purple/blue
C. Green
D. Yellow
Rationale: Gram-positive bacteria retain the crystal violet stain and appear
purple/blue under the microscope. Gram-negative bacteria appear red/pink because
they do not retain the crystal violet stain.
Guide Exam Prep Microorganisms •
Bacteria • Viruses • Fungi • Parasites •
Infection Control • Clinical
Applications Review
SECTION I: INTRODUCTION TO MICROBIOLOGY &
MICROORGANISM CLASSIFICATION (Questions 1–25)
1. A nurse is reviewing the characteristics of microorganisms. Which
statement best describes prokaryotes?
A. They have a true nucleus and membrane-bound organelles
B. They lack a true nucleus and membrane-bound organelles
C. They are larger than eukaryotic cells
D. They reproduce only sexually
Rationale: Prokaryotes (bacteria) lack a true nucleus and membrane-bound
organelles. Their genetic material is contained in a single circular chromosome in
the nucleoid region. Eukaryotes (fungi, protozoa, helminths) have a true nucleus
and membrane-bound organelles.
2. A nurse is teaching a student about the classification of microorganisms.
Which microorganism is classified as a prokaryote?
A. Fungi
B. Protozoa
C. Bacteria
D. Helminths
,Rationale: Bacteria are prokaryotes, meaning they lack a true nucleus and
membrane-bound organelles. Fungi, protozoa, and helminths are eukaryotes.
3. A nurse is reviewing the characteristics of viruses. Which statement best
describes viruses?
A. They are living cells that can reproduce independently
B. They are obligate intracellular parasites that require a host cell to replicate
C. They contain both DNA and RNA simultaneously
D. They are larger than bacteria
Rationale: Viruses are obligate intracellular parasites that require a host cell to
replicate. They contain either DNA or RNA, not both, and are much smaller than
bacteria.
4. A nurse is teaching about the classification of microorganisms. Which
microorganism is classified as a eukaryote?
A. Bacteria
B. Fungi
C. Viruses
D. Prions
Rationale: Fungi are eukaryotes, meaning they have a true nucleus and
membrane-bound organelles. Bacteria are prokaryotes, viruses are acellular, and
prions are infectious proteins.
5. A nurse is reviewing the structure of bacteria. Which structure is
responsible for bacterial motility?
A. Pili
B. Capsule
,C. Flagella
D. Cell wall
Rationale: Flagella are long, whip-like appendages that provide motility for
bacteria. Pili are involved in attachment and conjugation, the capsule provides
protection, and the cell wall provides structural support.
6. A nurse is reviewing the structure of bacteria. Which structure helps
bacteria adhere to surfaces and resist phagocytosis?
A. Flagella
B. Capsule
C. Ribosomes
D. Nucleoid
Rationale: The capsule is a polysaccharide layer outside the cell wall that helps
bacteria adhere to surfaces and resist phagocytosis by host immune cells.
7. A nurse is reviewing the structure of bacteria. Which structure is involved
in horizontal gene transfer between bacteria?
A. Flagella
B. Capsule
C. Pili
D. Cell membrane
Rationale: Pili (sex pili) are involved in conjugation, a form of horizontal gene
transfer where genetic material is transferred between bacteria.
8. A nurse is reviewing the classification of bacteria by shape. Which term
describes spherical bacteria?
, A. Bacilli
B. Cocci
C. Spirilla
D. Vibrios
Rationale: Cocci are spherical bacteria. Bacilli are rod-shaped, spirilla are spiral-
shaped, and vibrios are comma-shaped.
9. A nurse is reviewing the classification of bacteria by shape. Which term
describes rod-shaped bacteria?
A. Cocci
B. Bacilli
C. Spirilla
D. Spirochetes
Rationale: Bacilli are rod-shaped bacteria. Cocci are spherical, spirilla are spiral-
shaped, and spirochetes are flexible spiral-shaped bacteria.
10. A nurse is reviewing the classification of bacteria by Gram stain. Which
color indicates Gram-positive bacteria?
A. Red/pink
B. Purple/blue
C. Green
D. Yellow
Rationale: Gram-positive bacteria retain the crystal violet stain and appear
purple/blue under the microscope. Gram-negative bacteria appear red/pink because
they do not retain the crystal violet stain.
