DIAGNOSTIC MICROBIOLOGY, 7TH EDITION
CONNIE R. MAHON | VERIFIED CHAPTERS 1–
41 | 320 EXAM QUESTIONS
PART 1: INTRODUCTION TO CLINICAL MICROBIOLOGY
Chapter 1: Bacterial Cell Structure, Physiology, Metabolism, and Genetics
1. Which structure is responsible for the rigid shape of a bacterial cell and
provides protection against osmotic lysis?
A) Cytoplasmic membrane
B) Capsule
C) Cell wall
D) Nucleoid
Correct Answer: C
2. The cytoplasmic membrane of bacteria is composed primarily of:
A) Peptidoglycan
B) A phospholipid bilayer with embedded proteins
C) Lipopolysaccharide
D) Teichoic acid
Correct Answer: B
,3. Grampositive bacteria differ from Gramnegative bacteria primarily in the:
A) Presence of ribosomes
B) Thickness of the peptidoglycan layer
C) Type of nucleic acid
D) Method of reproduction
Correct Answer: B
4. Lipopolysaccharide (LPS) is an important virulence factor found in:
A) Grampositive bacteria
B) Gramnegative bacteria
C) Mycoplasma
D) Viruses
Correct Answer: B
5. The bacterial structure responsible for adherence to host tissues and
evasion of phagocytosis is the:
A) Flagella
B) Capsule
C) Pili
D) Endospore
Correct Answer: B
6. Plasmids are:
A) Essential for bacterial survival
B) Extrachromosomal DNA molecules that can carry antibiotic resistance
genes
,C) Part of the bacterial chromosome
D) Found only in Grampositive bacteria
Correct Answer: B
7. The term "generation time" refers to:
A) The time required for a bacterial population to double
B) The time required for a bacterial cell to die
C) The time required for DNA replication
D) The time required for spore formation
Correct Answer: A
8. Which of the following describes the bacterial growth phase where the
number of dying cells equals the number of new cells formed?
A) Lag phase
B) Log phase
C) Stationary phase
D) Death phase
Correct Answer: C
9. Binary fission in bacteria results in:
A) Two genetically identical daughter cells
B) Four genetically diverse daughter cells
C) One daughter cell and one parent cell
D) Eight daughter cells
Correct Answer: A
, 10. Bacteria that require oxygen for growth are called:
A) Anaerobes
B) Microaerophiles
C) Obligate aerobes
D) Facultative anaerobes
Correct Answer: C
11. The bacterial enzyme catalase is used to:
A) Produce oxygen from hydrogen peroxide
B) Convert nitrate to nitrite
C) Break down glucose
D) Synthesize peptidoglycan
Correct Answer: A
12. Transformation in bacteria refers to:
A) Transfer of DNA via a bacteriophage
B) Uptake of naked DNA from the environment
C) Direct celltocell transfer of DNA
D) Mutation of bacterial genes
Correct Answer: B
13. Bacterial endospores are:
A) Reproductive structures
B) Dormant forms resistant to heat and chemicals
CONNIE R. MAHON | VERIFIED CHAPTERS 1–
41 | 320 EXAM QUESTIONS
PART 1: INTRODUCTION TO CLINICAL MICROBIOLOGY
Chapter 1: Bacterial Cell Structure, Physiology, Metabolism, and Genetics
1. Which structure is responsible for the rigid shape of a bacterial cell and
provides protection against osmotic lysis?
A) Cytoplasmic membrane
B) Capsule
C) Cell wall
D) Nucleoid
Correct Answer: C
2. The cytoplasmic membrane of bacteria is composed primarily of:
A) Peptidoglycan
B) A phospholipid bilayer with embedded proteins
C) Lipopolysaccharide
D) Teichoic acid
Correct Answer: B
,3. Grampositive bacteria differ from Gramnegative bacteria primarily in the:
A) Presence of ribosomes
B) Thickness of the peptidoglycan layer
C) Type of nucleic acid
D) Method of reproduction
Correct Answer: B
4. Lipopolysaccharide (LPS) is an important virulence factor found in:
A) Grampositive bacteria
B) Gramnegative bacteria
C) Mycoplasma
D) Viruses
Correct Answer: B
5. The bacterial structure responsible for adherence to host tissues and
evasion of phagocytosis is the:
A) Flagella
B) Capsule
C) Pili
D) Endospore
Correct Answer: B
6. Plasmids are:
A) Essential for bacterial survival
B) Extrachromosomal DNA molecules that can carry antibiotic resistance
genes
,C) Part of the bacterial chromosome
D) Found only in Grampositive bacteria
Correct Answer: B
7. The term "generation time" refers to:
A) The time required for a bacterial population to double
B) The time required for a bacterial cell to die
C) The time required for DNA replication
D) The time required for spore formation
Correct Answer: A
8. Which of the following describes the bacterial growth phase where the
number of dying cells equals the number of new cells formed?
A) Lag phase
B) Log phase
C) Stationary phase
D) Death phase
Correct Answer: C
9. Binary fission in bacteria results in:
A) Two genetically identical daughter cells
B) Four genetically diverse daughter cells
C) One daughter cell and one parent cell
D) Eight daughter cells
Correct Answer: A
, 10. Bacteria that require oxygen for growth are called:
A) Anaerobes
B) Microaerophiles
C) Obligate aerobes
D) Facultative anaerobes
Correct Answer: C
11. The bacterial enzyme catalase is used to:
A) Produce oxygen from hydrogen peroxide
B) Convert nitrate to nitrite
C) Break down glucose
D) Synthesize peptidoglycan
Correct Answer: A
12. Transformation in bacteria refers to:
A) Transfer of DNA via a bacteriophage
B) Uptake of naked DNA from the environment
C) Direct celltocell transfer of DNA
D) Mutation of bacterial genes
Correct Answer: B
13. Bacterial endospores are:
A) Reproductive structures
B) Dormant forms resistant to heat and chemicals
