Chamberlain University
2 MAXE • 242 SOIB
★ ★
C College of Nursing & Public Health
J O U R N E Y T O E X T R A O R D I N A R Y CO M PA S S I O N AT E C A R E
EST. 1889
BIOS 242 — Examination 2 (Refined)
F U N D A M E N TA LS O F M I C R O B I O LO G Y: M E TA B O L I S M , A N T I M I C R O B I A LS & I N F E C T I O N
INSTITUTION Chamberlain University COURSE CODE BIOS 242
PROGRAM Bachelor of Science in Nursing (BSN) ACADEMIC YEAR
EXAM TITLE Examination 2 – Metabolism, Antimicrobials & Infection TOTAL QUESTIONS 40 Questions
COURSE TITLE Fundamentals of Microbiology FORMAT Multiple Choice — Select the Single Best Answer
EXAMINATION INSTRUCTIONS
▸ Select the single best answer for each multiple-choice question.
▸ This refined examination covers microbial nutritional and physical requirements, aerobic respiration vs. fermentation, antimicrobial drug modes of action, infection control
terminology, enzyme function, and the bacterial growth curve.
▸ Questions are drawn from the complete BIOS 242 Exam 2 refined review content.
▸ Correct answers and detailed rationales appear below each question for comprehensive review.
▸ All content reflects Chamberlain University BIOS 242 course competencies and learning objectives.
MICROBIAL METABOLISM, ANTIMICROBIALS & INFECTIOUS DISEASE Questions 1 – 40
1. A newly discovered microorganism that does not use oxygen, grows at pH 10 in hot springs, is green in color, and uses CO₂ as its carbon source would be described
as which combination of characteristics?
A. Aerobe, acidophile, mesophile, chemoheterotroph
B. Anaerobe, alkalinophile, thermophile, photoautotroph
C. Facultative anaerobe, neutrophile, psychrophile, chemoautotroph
D. Microaerophile, halophile, mesophile, photoheterotroph
CORRECT ANSWER B — Anaerobe, alkalinophile, thermophile, photoautotroph
RATIONALE The organism does not use O₂ (anaerobe), grows at pH 10 (alkalinophile), lives in hot springs (thermophile), is green/uses CO₂ as carbon source (photoautotroph—
uses light energy and inorganic CO₂). Option A is incorrect—aerobic, acidic, moderate temperature, chemical energy. Option C uses wrong oxygen, pH,
temperature, and carbon classifications.
2. Which process yields the MOST ATP in aerobic respiration?
A. Glycolysis
B. Krebs cycle
C. Electron Transport Chain
D. Fermentation
CORRECT ANSWER C — Electron Transport Chain
RATIONALE The Electron Transport Chain (ETC) produces approximately 34 ATP per glucose molecule through oxidative phosphorylation—the vast majority of ATP in aerobic
respiration. Glycolysis (A) produces only 2 ATP. The Krebs cycle (B) produces 2 ATP. Fermentation (D) produces only 2 ATP total.
3. Where does glycolysis take place in microorganisms?
A. Mitochondria
B. Nucleus
C. Cytoplasm
D. Cell membrane
CORRECT ANSWER C — Cytoplasm
RATIONALE Glycolysis occurs in the cytoplasm of both prokaryotic and eukaryotic cells. It does not require oxygen or membrane-bound organelles. The Krebs cycle and
Electron Transport Chain (A) occur in the mitochondria of eukaryotes and at the cell membrane of prokaryotes.
4. Where are the Krebs cycle and Electron Transport Chain located in eukaryotic microorganisms?
A. Cytoplasm
B. Mitochondria
C. Nucleus
D. Ribosomes
CORRECT ANSWER B — Mitochondria
RATIONALE In eukaryotes, the Krebs cycle occurs in the mitochondrial matrix and the Electron Transport Chain is located in the inner mitochondrial membrane. In
prokaryotes, these processes occur in the cytoplasm and at the cell membrane, respectively. Glycolysis (A) occurs in the cytoplasm.
, 5. Fermentation produces how many net ATP per glucose molecule?
A. 36–38 ATP
B. 4 ATP
C. 2 ATP
D. 34 ATP
CORRECT ANSWER C — 2 ATP
RATIONALE Fermentation produces only 2 net ATP per glucose molecule through substrate-level phosphorylation during glycolysis. It is the least efficient but fastest ATP-
producing pathway. Aerobic respiration (A) produces 36–38 ATP. The ETC alone (D) produces 34 ATP.
6. What is the final electron acceptor in aerobic respiration?
A. Nitrate (NO₃⁻)
B. Oxygen (O₂)
C. Pyruvate
D. NADH
CORRECT ANSWER B — Oxygen (O₂)
RATIONALE In aerobic respiration, O₂ serves as the final electron acceptor at the end of the Electron Transport Chain, forming water (H₂O). Nitrate (A) is used in anaerobic
respiration. Pyruvate (C) is a substrate. NADH (D) is an electron carrier.
7. Water is produced during which part of aerobic respiration?
A. Glycolysis
B. Krebs cycle
C. Electron Transport Chain
D. Fermentation
CORRECT ANSWER C — Electron Transport Chain
RATIONALE Water is formed at the end of the Electron Transport Chain when oxygen accepts electrons and combines with hydrogen ions: O₂ + 4e⁻ + 4H⁺ → 2H₂O. The Krebs
cycle (B) produces CO₂, not H₂O. Glycolysis (A) produces pyruvate and 2 ATP.
8. Which part of aerobic respiration releases CO₂ and produces NADH?
A. Glycolysis
B. Krebs cycle
C. Electron Transport Chain
D. Fermentation
CORRECT ANSWER B — Krebs cycle
RATIONALE The Krebs cycle (citric acid cycle) releases CO₂ as a waste product and produces NADH and FADH₂ (electron carriers). It is the largest producer of cofactors (NADH,
FADH₂) that feed into the ETC. The ETC (C) consumes oxygen and produces water.
9. The complete destruction of all microbes, including endospores, is called:
A. Disinfection
B. Sterilization
C. Antisepsis
D. Sanitization
CORRECT ANSWER B — Sterilization
RATIONALE Sterilization is the complete destruction or removal of all viable microorganisms, including highly resistant bacterial endospores. Disinfection (A) kills most
microbes but not necessarily spores. Antisepsis (C) is disinfection of living tissue. Sanitization (D) reduces microbial numbers to safe levels.
10. A bacteriostatic drug is one at which microbes:
A. Are immediately killed upon exposure
B. Survive but are unable to grow and reproduce
C. Mutate and develop resistance
D. Become permanently dormant
CORRECT ANSWER B — Survive but are unable to grow and reproduce
RATIONALE Bacteriostatic agents inhibit bacterial growth and reproduction without immediately killing the organisms. The host's immune system then clears the infection.
Bactericidal agents (A) kill bacteria directly. This distinction is clinically important when treating immunocompromised patients who rely on bactericidal drugs.
11. Beta-lactam antibiotics such as penicillin interfere with bacterial:
A. Protein synthesis
B. DNA replication
C. Cell wall synthesis
D. Folic acid synthesis
CORRECT ANSWER C — Cell wall synthesis
RATIONALE Beta-lactam antibiotics (penicillin, cephalosporins) inhibit peptidoglycan cross-linking in bacterial cell wall synthesis, causing cell lysis. They target penicillin-
binding proteins. Protein synthesis (A) is targeted by tetracyclines. DNA replication (B) is targeted by fluoroquinolones. Folic acid synthesis (D) is targeted by sulfa
drugs.
2 MAXE • 242 SOIB
★ ★
C College of Nursing & Public Health
J O U R N E Y T O E X T R A O R D I N A R Y CO M PA S S I O N AT E C A R E
EST. 1889
BIOS 242 — Examination 2 (Refined)
F U N D A M E N TA LS O F M I C R O B I O LO G Y: M E TA B O L I S M , A N T I M I C R O B I A LS & I N F E C T I O N
INSTITUTION Chamberlain University COURSE CODE BIOS 242
PROGRAM Bachelor of Science in Nursing (BSN) ACADEMIC YEAR
EXAM TITLE Examination 2 – Metabolism, Antimicrobials & Infection TOTAL QUESTIONS 40 Questions
COURSE TITLE Fundamentals of Microbiology FORMAT Multiple Choice — Select the Single Best Answer
EXAMINATION INSTRUCTIONS
▸ Select the single best answer for each multiple-choice question.
▸ This refined examination covers microbial nutritional and physical requirements, aerobic respiration vs. fermentation, antimicrobial drug modes of action, infection control
terminology, enzyme function, and the bacterial growth curve.
▸ Questions are drawn from the complete BIOS 242 Exam 2 refined review content.
▸ Correct answers and detailed rationales appear below each question for comprehensive review.
▸ All content reflects Chamberlain University BIOS 242 course competencies and learning objectives.
MICROBIAL METABOLISM, ANTIMICROBIALS & INFECTIOUS DISEASE Questions 1 – 40
1. A newly discovered microorganism that does not use oxygen, grows at pH 10 in hot springs, is green in color, and uses CO₂ as its carbon source would be described
as which combination of characteristics?
A. Aerobe, acidophile, mesophile, chemoheterotroph
B. Anaerobe, alkalinophile, thermophile, photoautotroph
C. Facultative anaerobe, neutrophile, psychrophile, chemoautotroph
D. Microaerophile, halophile, mesophile, photoheterotroph
CORRECT ANSWER B — Anaerobe, alkalinophile, thermophile, photoautotroph
RATIONALE The organism does not use O₂ (anaerobe), grows at pH 10 (alkalinophile), lives in hot springs (thermophile), is green/uses CO₂ as carbon source (photoautotroph—
uses light energy and inorganic CO₂). Option A is incorrect—aerobic, acidic, moderate temperature, chemical energy. Option C uses wrong oxygen, pH,
temperature, and carbon classifications.
2. Which process yields the MOST ATP in aerobic respiration?
A. Glycolysis
B. Krebs cycle
C. Electron Transport Chain
D. Fermentation
CORRECT ANSWER C — Electron Transport Chain
RATIONALE The Electron Transport Chain (ETC) produces approximately 34 ATP per glucose molecule through oxidative phosphorylation—the vast majority of ATP in aerobic
respiration. Glycolysis (A) produces only 2 ATP. The Krebs cycle (B) produces 2 ATP. Fermentation (D) produces only 2 ATP total.
3. Where does glycolysis take place in microorganisms?
A. Mitochondria
B. Nucleus
C. Cytoplasm
D. Cell membrane
CORRECT ANSWER C — Cytoplasm
RATIONALE Glycolysis occurs in the cytoplasm of both prokaryotic and eukaryotic cells. It does not require oxygen or membrane-bound organelles. The Krebs cycle and
Electron Transport Chain (A) occur in the mitochondria of eukaryotes and at the cell membrane of prokaryotes.
4. Where are the Krebs cycle and Electron Transport Chain located in eukaryotic microorganisms?
A. Cytoplasm
B. Mitochondria
C. Nucleus
D. Ribosomes
CORRECT ANSWER B — Mitochondria
RATIONALE In eukaryotes, the Krebs cycle occurs in the mitochondrial matrix and the Electron Transport Chain is located in the inner mitochondrial membrane. In
prokaryotes, these processes occur in the cytoplasm and at the cell membrane, respectively. Glycolysis (A) occurs in the cytoplasm.
, 5. Fermentation produces how many net ATP per glucose molecule?
A. 36–38 ATP
B. 4 ATP
C. 2 ATP
D. 34 ATP
CORRECT ANSWER C — 2 ATP
RATIONALE Fermentation produces only 2 net ATP per glucose molecule through substrate-level phosphorylation during glycolysis. It is the least efficient but fastest ATP-
producing pathway. Aerobic respiration (A) produces 36–38 ATP. The ETC alone (D) produces 34 ATP.
6. What is the final electron acceptor in aerobic respiration?
A. Nitrate (NO₃⁻)
B. Oxygen (O₂)
C. Pyruvate
D. NADH
CORRECT ANSWER B — Oxygen (O₂)
RATIONALE In aerobic respiration, O₂ serves as the final electron acceptor at the end of the Electron Transport Chain, forming water (H₂O). Nitrate (A) is used in anaerobic
respiration. Pyruvate (C) is a substrate. NADH (D) is an electron carrier.
7. Water is produced during which part of aerobic respiration?
A. Glycolysis
B. Krebs cycle
C. Electron Transport Chain
D. Fermentation
CORRECT ANSWER C — Electron Transport Chain
RATIONALE Water is formed at the end of the Electron Transport Chain when oxygen accepts electrons and combines with hydrogen ions: O₂ + 4e⁻ + 4H⁺ → 2H₂O. The Krebs
cycle (B) produces CO₂, not H₂O. Glycolysis (A) produces pyruvate and 2 ATP.
8. Which part of aerobic respiration releases CO₂ and produces NADH?
A. Glycolysis
B. Krebs cycle
C. Electron Transport Chain
D. Fermentation
CORRECT ANSWER B — Krebs cycle
RATIONALE The Krebs cycle (citric acid cycle) releases CO₂ as a waste product and produces NADH and FADH₂ (electron carriers). It is the largest producer of cofactors (NADH,
FADH₂) that feed into the ETC. The ETC (C) consumes oxygen and produces water.
9. The complete destruction of all microbes, including endospores, is called:
A. Disinfection
B. Sterilization
C. Antisepsis
D. Sanitization
CORRECT ANSWER B — Sterilization
RATIONALE Sterilization is the complete destruction or removal of all viable microorganisms, including highly resistant bacterial endospores. Disinfection (A) kills most
microbes but not necessarily spores. Antisepsis (C) is disinfection of living tissue. Sanitization (D) reduces microbial numbers to safe levels.
10. A bacteriostatic drug is one at which microbes:
A. Are immediately killed upon exposure
B. Survive but are unable to grow and reproduce
C. Mutate and develop resistance
D. Become permanently dormant
CORRECT ANSWER B — Survive but are unable to grow and reproduce
RATIONALE Bacteriostatic agents inhibit bacterial growth and reproduction without immediately killing the organisms. The host's immune system then clears the infection.
Bactericidal agents (A) kill bacteria directly. This distinction is clinically important when treating immunocompromised patients who rely on bactericidal drugs.
11. Beta-lactam antibiotics such as penicillin interfere with bacterial:
A. Protein synthesis
B. DNA replication
C. Cell wall synthesis
D. Folic acid synthesis
CORRECT ANSWER C — Cell wall synthesis
RATIONALE Beta-lactam antibiotics (penicillin, cephalosporins) inhibit peptidoglycan cross-linking in bacterial cell wall synthesis, causing cell lysis. They target penicillin-
binding proteins. Protein synthesis (A) is targeted by tetracyclines. DNA replication (B) is targeted by fluoroquinolones. Folic acid synthesis (D) is targeted by sulfa
drugs.
