BIOD 171
Microbiology
Module 1 Examination
Portage Learning | 2026/2027 Actual Exam
This comprehensive Module 1 examination covers the foundational concepts of
microbiology, including the history and pioneers of the field, microscopy and
specimen preparation, microbial classification and taxonomy, prokaryotic and
eukaryotic cell structure, microbial growth and metabolism, and physical and
chemical methods of microbial control. Each question is accompanied by a
detailed rationale that verifies the answer against Portage Learning BIOD 171
course materials.
Total Questions 100
Format Multiple Choice (A-D)
Sections 7
Coverage Module 1: Introductory Microbiology
Answer Key Verified with Detailed Rationales
Audience Portage Learning BIOD 171 Students
Section Breakdown
Section Question Range Topic
Section 1 Q1-Q15 Introduction to Microbiology and the Microbial World
Section 2 Q16-Q32 Microscopy and Specimen Preparation
Page 1 | BIOD 171 Module 1 | Portage Learning 2026/2027
,BIOD 171 Microbiology Module 1 Exam | Portage Learning 2026/2027 Actual Exam - Verified Answers
Section 3 Q33-Q48 Microbial Classification and Taxonomy
Section 4 Q49-Q66 Prokaryotic Cell Structure - Bacteria and Archaea
Section 5 Q67-Q80 Eukaryotic Microbial Structure
Section 6 Q81-Q94 Microbial Growth, Nutrition, and Metabolism
Section 7 Q95-Q100 Microbial Control and Sterilization
Verified | Comprehensive | Aligned with 2026/2027 Curriculum
Page 2 | BIOD 171 Module 1 | Portage Learning 2026/2027
,BIOD 171 Microbiology Module 1 Exam | Portage Learning 2026/2027 Actual Exam - Verified Answers
Examination Instructions: This exam contains 100 multiple-choice questions divided into seven sections
covering foundational microbiology topics. Each question has four answer options (A-D) with exactly one
correct answer. The correct answer is marked with [CORRECT] and listed as "Correct Answer: X". A
detailed rationale follows each question, explaining the microbiological reasoning behind the correct
answer and why the distractors are incorrect. Rationales are verified against Portage Learning BIOD 171
Module 1 course materials.
Section 1: Introduction to Microbiology and the Microbial World
(History, Pioneers, & Scope of Microbiology) - Q1-15
Q1: Who is credited as the first person to observe and document live microorganisms using a
hand-ground single-lens microscope, calling them "animalcules"?
A. Alexander Fleming, who visualized Penicillium mold inhibiting staphylococci
B. Antonie van Leeuwenhoek, who examined dental scrapings and pond water with
single-lens microscopes capable of ~300x magnification [CORRECT]
C. Robert Koch, who cultured bacteria on solid media
D. Louis Pasteur, who observed microbes in spoiled wine
Correct Answer: B - Antonie van Leeuwenhoek, who examined dental scrapings and pond water
with single-lens microscopes capable of ...
Rationale: Antonie van Leeuwenhoek (1632-1723), a Dutch draper, crafted single-lens microscopes achieving
~200-300x magnification and was the first to document bacteria, protists, and sperm cells, which he termed
"animalcules." Pasteur and Koch worked two centuries later with compound microscopes; Fleming's work
concerned antibiotic discovery. Verified against BIOD 171 Module 1 pioneer coverage.
Q2: Louis Pasteur's swan-neck flask experiment (1861) is most celebrated for definitively
disproving which theory?
A. The theory of biogenesis proposed by Francesco Redi
B. The theory of spontaneous generation, by showing microbes arose only from preexisting
microbes carried in air [CORRECT]
C. The germ theory of disease, by proving bacteria cause anthrax
D. The cell theory proposed by Schleiden and Schwann
Correct Answer: B - The theory of spontaneous generation, by showing microbes arose only from
preexisting microbes carried in air
Rationale: Pasteur's swan-neck flasks allowed air but not airborne microbes to enter boiled broth; the broth
remained sterile unless the flask was tilted so microbe-laden dust contacted it. This disproved spontaneous
generation (life arising from nonliving matter). Redi had earlier challenged it with meat/jar experiments; Koch's
postulates later formalized germ theory. Verified against BIOD 171 Module 1 history content.
Q3: A microbiology student is asked to identify the FOUR criteria that collectively constitute
Koch's postulates. Which set is correct?
Page 3 | BIOD 171 Module 1 | Portage Learning 2026/2027
, BIOD 171 Microbiology Module 1 Exam | Portage Learning 2026/2027 Actual Exam - Verified Answers
A. (1) microbe stains Gram-positive, (2) grows on blood agar, (3) produces toxin, (4) is killed by
penicillin
B. (1) disease occurs only in humans, (2) microbe is airborne, (3) vaccines prevent it, (4) antibiotics
cure it
C. (1) microbe is aerobic, (2) ferments glucose, (3) forms spores, (4) is motile
D. (1) microbe found in every diseased case, (2) isolated in pure culture, (3) causes disease
when reinoculated into a healthy susceptible host, (4) re-isolated from the experimentally
infected host and shown to be identical [CORRECT]
Correct Answer: D - (1) microbe found in every diseased case, (2) isolated in pure culture, (3)
causes disease when reinoculated i...
Rationale: Koch's postulates (1884) require: (1) the suspected pathogen is present in every diseased individual
and absent in healthy ones; (2) it must be isolated and grown in pure culture; (3) the pure culture must cause the
same disease when inoculated into a healthy susceptible host; (4) the pathogen must be re-isolated from the
newly diseased host and identified as identical to the original. Verified against BIOD 171 Module 1 pioneer
contributions.
Q4: Alexander Fleming's 1928 discovery of penicillin is best classified under which milestone
in microbiology?
A. The first widely used chemotherapeutic antibiotic derived from a microbial product
(Penicillium notatum) [CORRECT]
B. The first development of a solid medium for isolating pure bacterial cultures
C. The first formulation of aseptic surgery using carbolic acid
D. The first demonstration of vaccination using cowpox to protect against smallpox
Correct Answer: A - The first widely used chemotherapeutic antibiotic derived from a microbial
product (Penicillium notatum)
Rationale: Fleming observed that a Penicillium notatum mold contaminant inhibited Staphylococcus growth on
an agar plate, identifying the antibacterial substance penicillin - the first true antibiotic (microbial-derived
chemotherapeutic agent). Vaccination was pioneered by Edward Jenner (1796); aseptic surgery by Joseph Lister
(1867); solid media by Robert Koch and Angelina Hesse. Verified against BIOD 171 Module 1 antibiotic discovery
content.
Q5: Which application correctly matches a branch of microbiology with its industrial or
environmental role?
A. Medical microbiology - bioremediation of oil spills using Pseudomonas
B. Industrial microbiology - diagnosing tuberculosis using acid-fast staining
C. Food microbiology - manufacturing yogurt and cheese via Lactobacillus and
Streptococcus fermentation [CORRECT]
D. Environmental microbiology - producing insulin through recombinant E. coli
Correct Answer: C - Food microbiology - manufacturing yogurt and cheese via Lactobacillus and
Streptococcus fermentation
Rationale: Food microbiology employs lactic acid bacteria (Lactobacillus bulgaricus, Streptococcus thermophilus)
to ferment lactose into lactic acid, producing yogurt and cheese. Recombinant insulin (A) is
industrial/pharmaceutical microbiology. Oil-spill bioremediation (C) is environmental. TB diagnosis (D) is medical.
Page 4 | BIOD 171 Module 1 | Portage Learning 2026/2027
Microbiology
Module 1 Examination
Portage Learning | 2026/2027 Actual Exam
This comprehensive Module 1 examination covers the foundational concepts of
microbiology, including the history and pioneers of the field, microscopy and
specimen preparation, microbial classification and taxonomy, prokaryotic and
eukaryotic cell structure, microbial growth and metabolism, and physical and
chemical methods of microbial control. Each question is accompanied by a
detailed rationale that verifies the answer against Portage Learning BIOD 171
course materials.
Total Questions 100
Format Multiple Choice (A-D)
Sections 7
Coverage Module 1: Introductory Microbiology
Answer Key Verified with Detailed Rationales
Audience Portage Learning BIOD 171 Students
Section Breakdown
Section Question Range Topic
Section 1 Q1-Q15 Introduction to Microbiology and the Microbial World
Section 2 Q16-Q32 Microscopy and Specimen Preparation
Page 1 | BIOD 171 Module 1 | Portage Learning 2026/2027
,BIOD 171 Microbiology Module 1 Exam | Portage Learning 2026/2027 Actual Exam - Verified Answers
Section 3 Q33-Q48 Microbial Classification and Taxonomy
Section 4 Q49-Q66 Prokaryotic Cell Structure - Bacteria and Archaea
Section 5 Q67-Q80 Eukaryotic Microbial Structure
Section 6 Q81-Q94 Microbial Growth, Nutrition, and Metabolism
Section 7 Q95-Q100 Microbial Control and Sterilization
Verified | Comprehensive | Aligned with 2026/2027 Curriculum
Page 2 | BIOD 171 Module 1 | Portage Learning 2026/2027
,BIOD 171 Microbiology Module 1 Exam | Portage Learning 2026/2027 Actual Exam - Verified Answers
Examination Instructions: This exam contains 100 multiple-choice questions divided into seven sections
covering foundational microbiology topics. Each question has four answer options (A-D) with exactly one
correct answer. The correct answer is marked with [CORRECT] and listed as "Correct Answer: X". A
detailed rationale follows each question, explaining the microbiological reasoning behind the correct
answer and why the distractors are incorrect. Rationales are verified against Portage Learning BIOD 171
Module 1 course materials.
Section 1: Introduction to Microbiology and the Microbial World
(History, Pioneers, & Scope of Microbiology) - Q1-15
Q1: Who is credited as the first person to observe and document live microorganisms using a
hand-ground single-lens microscope, calling them "animalcules"?
A. Alexander Fleming, who visualized Penicillium mold inhibiting staphylococci
B. Antonie van Leeuwenhoek, who examined dental scrapings and pond water with
single-lens microscopes capable of ~300x magnification [CORRECT]
C. Robert Koch, who cultured bacteria on solid media
D. Louis Pasteur, who observed microbes in spoiled wine
Correct Answer: B - Antonie van Leeuwenhoek, who examined dental scrapings and pond water
with single-lens microscopes capable of ...
Rationale: Antonie van Leeuwenhoek (1632-1723), a Dutch draper, crafted single-lens microscopes achieving
~200-300x magnification and was the first to document bacteria, protists, and sperm cells, which he termed
"animalcules." Pasteur and Koch worked two centuries later with compound microscopes; Fleming's work
concerned antibiotic discovery. Verified against BIOD 171 Module 1 pioneer coverage.
Q2: Louis Pasteur's swan-neck flask experiment (1861) is most celebrated for definitively
disproving which theory?
A. The theory of biogenesis proposed by Francesco Redi
B. The theory of spontaneous generation, by showing microbes arose only from preexisting
microbes carried in air [CORRECT]
C. The germ theory of disease, by proving bacteria cause anthrax
D. The cell theory proposed by Schleiden and Schwann
Correct Answer: B - The theory of spontaneous generation, by showing microbes arose only from
preexisting microbes carried in air
Rationale: Pasteur's swan-neck flasks allowed air but not airborne microbes to enter boiled broth; the broth
remained sterile unless the flask was tilted so microbe-laden dust contacted it. This disproved spontaneous
generation (life arising from nonliving matter). Redi had earlier challenged it with meat/jar experiments; Koch's
postulates later formalized germ theory. Verified against BIOD 171 Module 1 history content.
Q3: A microbiology student is asked to identify the FOUR criteria that collectively constitute
Koch's postulates. Which set is correct?
Page 3 | BIOD 171 Module 1 | Portage Learning 2026/2027
, BIOD 171 Microbiology Module 1 Exam | Portage Learning 2026/2027 Actual Exam - Verified Answers
A. (1) microbe stains Gram-positive, (2) grows on blood agar, (3) produces toxin, (4) is killed by
penicillin
B. (1) disease occurs only in humans, (2) microbe is airborne, (3) vaccines prevent it, (4) antibiotics
cure it
C. (1) microbe is aerobic, (2) ferments glucose, (3) forms spores, (4) is motile
D. (1) microbe found in every diseased case, (2) isolated in pure culture, (3) causes disease
when reinoculated into a healthy susceptible host, (4) re-isolated from the experimentally
infected host and shown to be identical [CORRECT]
Correct Answer: D - (1) microbe found in every diseased case, (2) isolated in pure culture, (3)
causes disease when reinoculated i...
Rationale: Koch's postulates (1884) require: (1) the suspected pathogen is present in every diseased individual
and absent in healthy ones; (2) it must be isolated and grown in pure culture; (3) the pure culture must cause the
same disease when inoculated into a healthy susceptible host; (4) the pathogen must be re-isolated from the
newly diseased host and identified as identical to the original. Verified against BIOD 171 Module 1 pioneer
contributions.
Q4: Alexander Fleming's 1928 discovery of penicillin is best classified under which milestone
in microbiology?
A. The first widely used chemotherapeutic antibiotic derived from a microbial product
(Penicillium notatum) [CORRECT]
B. The first development of a solid medium for isolating pure bacterial cultures
C. The first formulation of aseptic surgery using carbolic acid
D. The first demonstration of vaccination using cowpox to protect against smallpox
Correct Answer: A - The first widely used chemotherapeutic antibiotic derived from a microbial
product (Penicillium notatum)
Rationale: Fleming observed that a Penicillium notatum mold contaminant inhibited Staphylococcus growth on
an agar plate, identifying the antibacterial substance penicillin - the first true antibiotic (microbial-derived
chemotherapeutic agent). Vaccination was pioneered by Edward Jenner (1796); aseptic surgery by Joseph Lister
(1867); solid media by Robert Koch and Angelina Hesse. Verified against BIOD 171 Module 1 antibiotic discovery
content.
Q5: Which application correctly matches a branch of microbiology with its industrial or
environmental role?
A. Medical microbiology - bioremediation of oil spills using Pseudomonas
B. Industrial microbiology - diagnosing tuberculosis using acid-fast staining
C. Food microbiology - manufacturing yogurt and cheese via Lactobacillus and
Streptococcus fermentation [CORRECT]
D. Environmental microbiology - producing insulin through recombinant E. coli
Correct Answer: C - Food microbiology - manufacturing yogurt and cheese via Lactobacillus and
Streptococcus fermentation
Rationale: Food microbiology employs lactic acid bacteria (Lactobacillus bulgaricus, Streptococcus thermophilus)
to ferment lactose into lactic acid, producing yogurt and cheese. Recombinant insulin (A) is
industrial/pharmaceutical microbiology. Oil-spill bioremediation (C) is environmental. TB diagnosis (D) is medical.
Page 4 | BIOD 171 Module 1 | Portage Learning 2026/2027
