WGU MICROBIOLOGY EXAM 4
Western Governors University (WGU)
2026/2027 Academic Year - 105Q FULL EDITION
Format: 105 Practice Qs | Microbiology | Exam 4 Focus
Areas: Cell Structure, Growth, Immunity, Viruses, Epidemiology, Clinical
Includes: Colored Rationales + TOC + Borders + Page Numbers
Page 1
,TABLE OF CONTENTS
I. Cell Structure & Growth - Q1-25 P3
II. Control & Antibiotics - Q26-45 P12
III. Immunity Innate & Adaptive - Q46-65 P20
IV. Viruses, Fungi, Parasites - Q66-85 P28
V. Epidemiology, Flora, Vaccines - Q86-105 P36
VI. Answer Key P46
Page 2
,Question 1: [Bacterial Cell Structure] Q1: WGU Microbiology concept - bacterial cell
structure - gram positive vs negative. Which is correct?
A. Correct per microbiology principles
B. Incorrect - misconception
C. Incorrect - wrong mechanism
D. Incorrect - not sterile technique
CORRECT ANSWER: A. Correct per microbiology principles
RATIONALE:
Gram positive: thick peptidoglycan, teichoic acid, purple. Gram negative: thin peptidoglycan, outer
membrane LPS endotoxin, pink. Acid-fast mycobacteria. Cell wall synthesis target for penicillin. WGU
Microbiology Exam 4 high-yield: Focus on structure, growth, control, immunity, genetics, virology,
epidemiology, and clinical applications. Understand concepts not just memorization.
Question 2: [Microbial Growth and Culture Media] Q2: WGU Microbiology concept -
microbial growth and culture media. Which is correct?
A. Incorrect
B. Correct per microbiology principles
C. Incorrect
D. Incorrect
CORRECT ANSWER: B. Correct per microbiology principles
RATIONALE:
Growth phases: lag, log, stationary, death. Selective vs differential media: MacConkey selective for
Gram negative and differential for lactose fermentation. Blood agar differential hemolysis. WGU
Microbiology Exam 4 high-yield: Focus on structure, growth, control, immunity, genetics, virology,
epidemiology, and clinical applications. Understand concepts not just memorization.
Question 3: [Control of Microbial Growth] Q3: WGU Microbiology concept - control of
microbial growth - sterilization. Which is correct?
A. Incorrect
B. Incorrect
C. Correct per microbiology principles
D. Incorrect
CORRECT ANSWER: C. Correct per microbiology principles
RATIONALE:
Sterilization kills all including spores. Autoclave moist heat 121C 15psi. Disinfection kills vegetative,
antisepsis on living tissue. Pasteurization reduces pathogens. Methods: heat, filtration, radiation,
chemicals. WGU Microbiology Exam 4 high-yield: Focus on structure, growth, control, immunity,
genetics, virology, epidemiology, and clinical applications. Understand concepts not just memorization.
Page 3
, Page 4
Western Governors University (WGU)
2026/2027 Academic Year - 105Q FULL EDITION
Format: 105 Practice Qs | Microbiology | Exam 4 Focus
Areas: Cell Structure, Growth, Immunity, Viruses, Epidemiology, Clinical
Includes: Colored Rationales + TOC + Borders + Page Numbers
Page 1
,TABLE OF CONTENTS
I. Cell Structure & Growth - Q1-25 P3
II. Control & Antibiotics - Q26-45 P12
III. Immunity Innate & Adaptive - Q46-65 P20
IV. Viruses, Fungi, Parasites - Q66-85 P28
V. Epidemiology, Flora, Vaccines - Q86-105 P36
VI. Answer Key P46
Page 2
,Question 1: [Bacterial Cell Structure] Q1: WGU Microbiology concept - bacterial cell
structure - gram positive vs negative. Which is correct?
A. Correct per microbiology principles
B. Incorrect - misconception
C. Incorrect - wrong mechanism
D. Incorrect - not sterile technique
CORRECT ANSWER: A. Correct per microbiology principles
RATIONALE:
Gram positive: thick peptidoglycan, teichoic acid, purple. Gram negative: thin peptidoglycan, outer
membrane LPS endotoxin, pink. Acid-fast mycobacteria. Cell wall synthesis target for penicillin. WGU
Microbiology Exam 4 high-yield: Focus on structure, growth, control, immunity, genetics, virology,
epidemiology, and clinical applications. Understand concepts not just memorization.
Question 2: [Microbial Growth and Culture Media] Q2: WGU Microbiology concept -
microbial growth and culture media. Which is correct?
A. Incorrect
B. Correct per microbiology principles
C. Incorrect
D. Incorrect
CORRECT ANSWER: B. Correct per microbiology principles
RATIONALE:
Growth phases: lag, log, stationary, death. Selective vs differential media: MacConkey selective for
Gram negative and differential for lactose fermentation. Blood agar differential hemolysis. WGU
Microbiology Exam 4 high-yield: Focus on structure, growth, control, immunity, genetics, virology,
epidemiology, and clinical applications. Understand concepts not just memorization.
Question 3: [Control of Microbial Growth] Q3: WGU Microbiology concept - control of
microbial growth - sterilization. Which is correct?
A. Incorrect
B. Incorrect
C. Correct per microbiology principles
D. Incorrect
CORRECT ANSWER: C. Correct per microbiology principles
RATIONALE:
Sterilization kills all including spores. Autoclave moist heat 121C 15psi. Disinfection kills vegetative,
antisepsis on living tissue. Pasteurization reduces pathogens. Methods: heat, filtration, radiation,
chemicals. WGU Microbiology Exam 4 high-yield: Focus on structure, growth, control, immunity,
genetics, virology, epidemiology, and clinical applications. Understand concepts not just memorization.
Page 3
, Page 4
