Chamberlain University
2 MAXE • 242 SOIB
★ ★
C College of Nursing & Health Professions
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
N U T R I T I O N , G R O W T H , M E TA B O L I S M , CO N T R O L , D R U G S & 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 — Fundamentals of Microbiology TOTAL QUESTIONS 25 Questions
COURSE TITLE Fundamentals of Microbiology FORMAT Multiple Choice — Select the Single Best Answer
EXAMINATION INSTRUCTIONS
▸ Select the single best answer for each question unless otherwise instructed.
▸ This comprehensive examination covers microbial nutrition, growth, metabolism, control methods, antimicrobial drugs, and infection.
▸ All content reflects BIOS 242 learning objectives and foundational microbiology for nursing practice.
▸ Correct answers and detailed rationales appear below each question for exam preparation purposes.
▸ Pay careful attention to drug mechanisms, metabolic pathway details, and epidemiological terminology.
SECTION I — NUTRITION, GROWTH, METABOLISM, CONTROL, DRUGS & INFECTION Questions 1 – 25
1. Heterotrophs are organisms that must obtain their carbon in organic form. Autotrophs differ in that they:
A. Are dependent on eating other life forms for carbon
B. Are "self-feeders" that use inorganic CO₂ as their carbon source to build organic compounds through photosynthesis or chemosynthesis
C. Obtain energy only from sunlight
D. Obtain energy only from chemical compounds
CORRECT ANSWER B — Are "self-feeders" that use inorganic CO₂ as their carbon source to build organic compounds through photosynthesis or chemosynthesis
RATIONALE Autotrophs are "self-feeders" — they use inorganic CO₂ as their carbon source and build organic compounds from it, either through photosynthesis
(photoautotrophs) or chemosynthesis (chemoautotrophs). Heterotrophs must obtain carbon in organic form and are dependent on consuming other life forms.
Phototrophs get energy from sunlight. Chemotrophs get energy from chemical compounds. These terms can be combined: photoautotrophs (light + CO₂),
chemoheterotrophs (chemicals + organic carbon — humans), chemoautotrophs (chemicals + CO₂ — methanogens). Saprobes obtain food from decaying organic
matter. Parasites live on/in another organism.
2. Cardinal temperatures describe the minimum, optimum, and maximum temperatures at which an organism grows. Psychrophiles are cold-loving microbes with
which temperature characteristics?
A. Optimum growth at 20–40°C — includes most human pathogens
B. Growth range 0–20°C, optimum at 15°C — found in arctic, antarctic, and ocean depths
C. General growth range 45°C to 80°C — heat-loving
D. Growth above 80°C and some above 100°C — hyperthermophiles
CORRECT ANSWER B — Growth range 0–20°C, optimum at 15°C — found in arctic, antarctic, and ocean depths
RATIONALE Psychrophiles are cold-loving microbes with a growth range of 0–20°C and optimal growth at 15°C. They are found in permanently cold environments. Mesophiles
grow best at 20–40°C and include the majority of medically significant organisms (human pathogens). Thermophiles have a general growth range of 45–80°C.
Hyperthermophiles are archaea growing above 80°C, some above 100°C. Maximum growth temperature is the highest at which growth is possible; minimum is the
lowest. Cardinal temperatures are critical for understanding organism ecology and infection potential.
3. Which of the following correctly pairs an environmental adaptation with the organism type?
A. Acidophiles — grow at extreme alkaline pH
B. Barophiles — can survive under extreme pressure and will rupture at normal atmospheric pressure
C. Halophiles — require acidic environments with low salt
D. Alkalinophiles — grow in acidic environments
CORRECT ANSWER B — Barophiles — can survive under extreme pressure and will rupture at normal atmospheric pressure
RATIONALE Barophiles are adapted to survive under extreme hydrostatic pressure (e.g., deep-sea microbes) and will rupture if exposed to normal atmospheric pressure.
Acidophiles grow in acidic environments; alkalinophiles grow at extreme alkaline pH. Halophiles are salt-loving archaea thriving in high salt concentrations. This
correct pairing of organism type with its environmental adaptation is essential for understanding microbial ecology and predicting where organisms can survive.
Other adaptations: aerobes require oxygen, anaerobes are destroyed by oxygen, facultative organisms switch between aerobic respiration and fermentation.
, 4. Symbiotic relationships include mutualism, commensalism, and parasitism. Which statement correctly distinguishes them?
A. Mutualism — both species benefit; Commensalism — one benefits, the other is unaffected; Parasitism — one benefits, the other is harmed
B. All three relationships result in harm to one organism
C. Mutualism and parasitism are identical; only commensalism is distinct
D. Commensalism always harms the host; mutualism benefits only one organism
CORRECT ANSWER A — Mutualism — both species benefit; Commensalism — one benefits, the other is unaffected; Parasitism — one benefits, the other is harmed
RATIONALE Symbiosis is a close relationship between two species. The three types are: Mutualism — both species benefit (e.g., gut bacteria producing vitamins while
receiving nutrients); Commensalism — one organism benefits while the other is unaffected (e.g., Staphylococcus on skin); Parasitism — one organism benefits at
the expense of the host, causing harm (e.g., helminths, many pathogens). Understanding these ecological relationships is fundamental to distinguishing between
normal biota, opportunistic pathogens, and true pathogens. Normal biota is the large, diverse collection of microbes living on and in the body.
5. An enzyme speeds up a reaction by lowering activation energy. The holoenzyme consists of:
A. Only the protein portion (apoenzyme)
B. A protein portion (apoenzyme) AND a nonprotein molecule (cofactor) — cofactors can be organic (coenzymes) or inorganic (metal ions)
C. Only organic vitamin components
D. Only inorganic metal ions without protein
CORRECT ANSWER B — A protein portion (apoenzyme) AND a nonprotein molecule (cofactor) — cofactors can be organic (coenzymes) or inorganic (metal ions)
RATIONALE A holoenzyme is the complete, functional enzyme consisting of: (1) the apoenzyme — the protein portion composed of amino acids; (2) a cofactor — a nonprotein
portion that can be organic (coenzymes — vitamins are important components) or inorganic (metal ions). The active site is where the substrate binds. Exoenzymes
are transported extracellularly to break down large food molecules. Endoenzymes are retained intracellularly. Constitutive enzymes are always present in constant
amounts. Regulated enzymes are induced or repressed based on substrate concentration. Competitive inhibition binds to the active site; non-competitive
inhibition binds elsewhere.
6. Glycolysis is the most common pathway used to break down glucose. It is the first step in all three catabolic pathways and takes place in the:
A. Mitochondrial matrix in both prokaryotes and eukaryotes
B. Cytoplasm — in both prokaryotes and eukaryotes
C. Cell membrane in prokaryotes; nucleus in eukaryotes
D. Endoplasmic reticulum in all cell types
CORRECT ANSWER B — Cytoplasm — in both prokaryotes and eukaryotes
RATIONALE Glycolysis occurs in the cytoplasm of both prokaryotes and eukaryotes. It is the first step common to all three main catabolic pathways (aerobic respiration,
anaerobic respiration, fermentation). The Krebs Cycle takes place in the mitochondrial matrix in eukaryotes and in the cytoplasm in prokaryotes — it is the major
producer of cofactors (NADH, FADH₂) and CO₂. The Electron Transport Chain occurs at the inner mitochondrial membrane in eukaryotes and the cytoplasmic
membrane in prokaryotes. Fermentation is the incomplete oxidation of glucose without oxygen, producing acids, alcohols, and CO₂ while regenerating NAD⁺.
7. Sterilization, disinfection, antisepsis, and decontamination represent different levels of microbial control. Which statement correctly matches the method with its
definition?
A. Sterilization — destroys most microbial life, reducing contamination on inanimate surfaces
B. Disinfection — the destruction of ALL microbial life including endospores
C. Antisepsis — destroys most microbial life, reducing contamination on a living surface (vegetative pathogens, not endospores)
D. Decontamination — completely destroys all microbial life on animate and inanimate surfaces
CORRECT ANSWER C — Antisepsis — destroys most microbial life, reducing contamination on a living surface (vegetative pathogens, not endospores)
RATIONALE Antisepsis destroys most microbial life on living surfaces, targeting vegetative pathogens but not endospores. Sterilization destroys ALL microbial life (including
endospores) on inanimate objects. Disinfection destroys most microbial life on inanimate surfaces (vegetative pathogens, not endospores).
Decontamination/sanitization mechanically removes most microbes from animate or inanimate surfaces, reducing contamination to safe levels. A bactericide
destroys bacteria except endospores. A bacteriostatic agent prevents growth without killing ("-static" = prevented from multiplying). A fungicide kills fungal
spores, hyphae, and yeasts.
8. Pasteurization is a disinfection method that uses mild heat (71.6°C). It destroys vegetative stages of bacteria and fungi but does NOT kill:
A. All microorganisms — it achieves complete sterilization
B. Endospores or heat-resistant microbes including lactobacilli, micrococci, and yeast
C. Only Gram-negative bacteria
D. Viruses — pasteurization targets only viruses
CORRECT ANSWER B — Endospores or heat-resistant microbes including lactobacilli, micrococci, and yeast
RATIONALE Pasteurization (71.6°C) is a disinfection method — it does NOT achieve sterilization. It destroys vegetative stages of bacteria and fungi but does NOT kill
endospores or heat-resistant microbes (lactobacilli, micrococci, yeast). Boiling (100°C) for 30 minutes kills most non-endospore-forming pathogens. Steam under
pressure (autoclaving: 121°C at 15 psi for 15 minutes) achieves sterilization. Incineration uses flame or hot air ovens. Desiccation dehydrates vegetative cells. Cold
treatment retards microbial activities but generally does not kill. Filtration physically removes microbes. HEPA filters remove 99.97% of particles ≥0.3 microns.
2 MAXE • 242 SOIB
★ ★
C College of Nursing & Health Professions
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
N U T R I T I O N , G R O W T H , M E TA B O L I S M , CO N T R O L , D R U G S & 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 — Fundamentals of Microbiology TOTAL QUESTIONS 25 Questions
COURSE TITLE Fundamentals of Microbiology FORMAT Multiple Choice — Select the Single Best Answer
EXAMINATION INSTRUCTIONS
▸ Select the single best answer for each question unless otherwise instructed.
▸ This comprehensive examination covers microbial nutrition, growth, metabolism, control methods, antimicrobial drugs, and infection.
▸ All content reflects BIOS 242 learning objectives and foundational microbiology for nursing practice.
▸ Correct answers and detailed rationales appear below each question for exam preparation purposes.
▸ Pay careful attention to drug mechanisms, metabolic pathway details, and epidemiological terminology.
SECTION I — NUTRITION, GROWTH, METABOLISM, CONTROL, DRUGS & INFECTION Questions 1 – 25
1. Heterotrophs are organisms that must obtain their carbon in organic form. Autotrophs differ in that they:
A. Are dependent on eating other life forms for carbon
B. Are "self-feeders" that use inorganic CO₂ as their carbon source to build organic compounds through photosynthesis or chemosynthesis
C. Obtain energy only from sunlight
D. Obtain energy only from chemical compounds
CORRECT ANSWER B — Are "self-feeders" that use inorganic CO₂ as their carbon source to build organic compounds through photosynthesis or chemosynthesis
RATIONALE Autotrophs are "self-feeders" — they use inorganic CO₂ as their carbon source and build organic compounds from it, either through photosynthesis
(photoautotrophs) or chemosynthesis (chemoautotrophs). Heterotrophs must obtain carbon in organic form and are dependent on consuming other life forms.
Phototrophs get energy from sunlight. Chemotrophs get energy from chemical compounds. These terms can be combined: photoautotrophs (light + CO₂),
chemoheterotrophs (chemicals + organic carbon — humans), chemoautotrophs (chemicals + CO₂ — methanogens). Saprobes obtain food from decaying organic
matter. Parasites live on/in another organism.
2. Cardinal temperatures describe the minimum, optimum, and maximum temperatures at which an organism grows. Psychrophiles are cold-loving microbes with
which temperature characteristics?
A. Optimum growth at 20–40°C — includes most human pathogens
B. Growth range 0–20°C, optimum at 15°C — found in arctic, antarctic, and ocean depths
C. General growth range 45°C to 80°C — heat-loving
D. Growth above 80°C and some above 100°C — hyperthermophiles
CORRECT ANSWER B — Growth range 0–20°C, optimum at 15°C — found in arctic, antarctic, and ocean depths
RATIONALE Psychrophiles are cold-loving microbes with a growth range of 0–20°C and optimal growth at 15°C. They are found in permanently cold environments. Mesophiles
grow best at 20–40°C and include the majority of medically significant organisms (human pathogens). Thermophiles have a general growth range of 45–80°C.
Hyperthermophiles are archaea growing above 80°C, some above 100°C. Maximum growth temperature is the highest at which growth is possible; minimum is the
lowest. Cardinal temperatures are critical for understanding organism ecology and infection potential.
3. Which of the following correctly pairs an environmental adaptation with the organism type?
A. Acidophiles — grow at extreme alkaline pH
B. Barophiles — can survive under extreme pressure and will rupture at normal atmospheric pressure
C. Halophiles — require acidic environments with low salt
D. Alkalinophiles — grow in acidic environments
CORRECT ANSWER B — Barophiles — can survive under extreme pressure and will rupture at normal atmospheric pressure
RATIONALE Barophiles are adapted to survive under extreme hydrostatic pressure (e.g., deep-sea microbes) and will rupture if exposed to normal atmospheric pressure.
Acidophiles grow in acidic environments; alkalinophiles grow at extreme alkaline pH. Halophiles are salt-loving archaea thriving in high salt concentrations. This
correct pairing of organism type with its environmental adaptation is essential for understanding microbial ecology and predicting where organisms can survive.
Other adaptations: aerobes require oxygen, anaerobes are destroyed by oxygen, facultative organisms switch between aerobic respiration and fermentation.
, 4. Symbiotic relationships include mutualism, commensalism, and parasitism. Which statement correctly distinguishes them?
A. Mutualism — both species benefit; Commensalism — one benefits, the other is unaffected; Parasitism — one benefits, the other is harmed
B. All three relationships result in harm to one organism
C. Mutualism and parasitism are identical; only commensalism is distinct
D. Commensalism always harms the host; mutualism benefits only one organism
CORRECT ANSWER A — Mutualism — both species benefit; Commensalism — one benefits, the other is unaffected; Parasitism — one benefits, the other is harmed
RATIONALE Symbiosis is a close relationship between two species. The three types are: Mutualism — both species benefit (e.g., gut bacteria producing vitamins while
receiving nutrients); Commensalism — one organism benefits while the other is unaffected (e.g., Staphylococcus on skin); Parasitism — one organism benefits at
the expense of the host, causing harm (e.g., helminths, many pathogens). Understanding these ecological relationships is fundamental to distinguishing between
normal biota, opportunistic pathogens, and true pathogens. Normal biota is the large, diverse collection of microbes living on and in the body.
5. An enzyme speeds up a reaction by lowering activation energy. The holoenzyme consists of:
A. Only the protein portion (apoenzyme)
B. A protein portion (apoenzyme) AND a nonprotein molecule (cofactor) — cofactors can be organic (coenzymes) or inorganic (metal ions)
C. Only organic vitamin components
D. Only inorganic metal ions without protein
CORRECT ANSWER B — A protein portion (apoenzyme) AND a nonprotein molecule (cofactor) — cofactors can be organic (coenzymes) or inorganic (metal ions)
RATIONALE A holoenzyme is the complete, functional enzyme consisting of: (1) the apoenzyme — the protein portion composed of amino acids; (2) a cofactor — a nonprotein
portion that can be organic (coenzymes — vitamins are important components) or inorganic (metal ions). The active site is where the substrate binds. Exoenzymes
are transported extracellularly to break down large food molecules. Endoenzymes are retained intracellularly. Constitutive enzymes are always present in constant
amounts. Regulated enzymes are induced or repressed based on substrate concentration. Competitive inhibition binds to the active site; non-competitive
inhibition binds elsewhere.
6. Glycolysis is the most common pathway used to break down glucose. It is the first step in all three catabolic pathways and takes place in the:
A. Mitochondrial matrix in both prokaryotes and eukaryotes
B. Cytoplasm — in both prokaryotes and eukaryotes
C. Cell membrane in prokaryotes; nucleus in eukaryotes
D. Endoplasmic reticulum in all cell types
CORRECT ANSWER B — Cytoplasm — in both prokaryotes and eukaryotes
RATIONALE Glycolysis occurs in the cytoplasm of both prokaryotes and eukaryotes. It is the first step common to all three main catabolic pathways (aerobic respiration,
anaerobic respiration, fermentation). The Krebs Cycle takes place in the mitochondrial matrix in eukaryotes and in the cytoplasm in prokaryotes — it is the major
producer of cofactors (NADH, FADH₂) and CO₂. The Electron Transport Chain occurs at the inner mitochondrial membrane in eukaryotes and the cytoplasmic
membrane in prokaryotes. Fermentation is the incomplete oxidation of glucose without oxygen, producing acids, alcohols, and CO₂ while regenerating NAD⁺.
7. Sterilization, disinfection, antisepsis, and decontamination represent different levels of microbial control. Which statement correctly matches the method with its
definition?
A. Sterilization — destroys most microbial life, reducing contamination on inanimate surfaces
B. Disinfection — the destruction of ALL microbial life including endospores
C. Antisepsis — destroys most microbial life, reducing contamination on a living surface (vegetative pathogens, not endospores)
D. Decontamination — completely destroys all microbial life on animate and inanimate surfaces
CORRECT ANSWER C — Antisepsis — destroys most microbial life, reducing contamination on a living surface (vegetative pathogens, not endospores)
RATIONALE Antisepsis destroys most microbial life on living surfaces, targeting vegetative pathogens but not endospores. Sterilization destroys ALL microbial life (including
endospores) on inanimate objects. Disinfection destroys most microbial life on inanimate surfaces (vegetative pathogens, not endospores).
Decontamination/sanitization mechanically removes most microbes from animate or inanimate surfaces, reducing contamination to safe levels. A bactericide
destroys bacteria except endospores. A bacteriostatic agent prevents growth without killing ("-static" = prevented from multiplying). A fungicide kills fungal
spores, hyphae, and yeasts.
8. Pasteurization is a disinfection method that uses mild heat (71.6°C). It destroys vegetative stages of bacteria and fungi but does NOT kill:
A. All microorganisms — it achieves complete sterilization
B. Endospores or heat-resistant microbes including lactobacilli, micrococci, and yeast
C. Only Gram-negative bacteria
D. Viruses — pasteurization targets only viruses
CORRECT ANSWER B — Endospores or heat-resistant microbes including lactobacilli, micrococci, and yeast
RATIONALE Pasteurization (71.6°C) is a disinfection method — it does NOT achieve sterilization. It destroys vegetative stages of bacteria and fungi but does NOT kill
endospores or heat-resistant microbes (lactobacilli, micrococci, yeast). Boiling (100°C) for 30 minutes kills most non-endospore-forming pathogens. Steam under
pressure (autoclaving: 121°C at 15 psi for 15 minutes) achieves sterilization. Incineration uses flame or hot air ovens. Desiccation dehydrates vegetative cells. Cold
treatment retards microbial activities but generally does not kill. Filtration physically removes microbes. HEPA filters remove 99.97% of particles ≥0.3 microns.
