PORTAGE LEARNING BIOD171 MICROBIOLOGY EXAMS 2026 | Modules 1–5 Complete Questions & Verified Answers | All Versions | A+ Study Guide

PORTAGE LEARNING BIOD171
MICROBIOLOGY EXAMS 2026 |
Modules 1–5 Complete Questions &
Verified Answers | All Versions | A+
Study Guide
PORTAGE LEARNING BIOD171 MICROBIOLOGY EXAMS 2026

Modules 1–5 | Complete Questions & Verified Answers | A+ Study Guide



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MODULE 1 — INTRODUCTION TO MICROBIOLOGY

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Question 1 What is microbiology?

A) The study of large organisms

B) The study of microorganisms including bacteria, viruses, fungi, and
parasites

C) The study of human anatomy

D) The study of chemical reactions only
E) The study of plant biology

CORRECT ANSWER: B RATIONALE: Microbiology is broadly defined as the study of
microorganisms — tiny living things invisible to the naked eye — including bacteria,
viruses, fungi, protozoa, algae, and parasites, as well as their effects on other living
organisms and the environment.



Question 2 Who is considered the "Father of Microbiology"?

A) Louis Pasteur
B) Robert Koch

, C) Antonie van Leeuwenhoek

D) Alexander Fleming

E) Joseph Lister

CORRECT ANSWER: C RATIONALE: Antonie van Leeuwenhoek was the first to
observe and describe microorganisms using his improved microscope in the 1670s,
earning him the title "Father of Microbiology."



Question 3 What instrument did Antonie van Leeuwenhoek use to first observe
microorganisms?

A) Electron microscope

B) Compound microscope

C) Simple microscope with a single lens

D) Telescope

E) Phase-contrast microscope

CORRECT ANSWER: C RATIONALE: Leeuwenhoek used a simple single-lens
microscope he crafted himself, achieving magnifications of up to 270×, which allowed
him to observe "animalcules" (microorganisms) for the first time.


Question 4 Louis Pasteur's experiments with swan-neck flasks disproved which theory?

A) Germ theory
B) Cell theory

C) Spontaneous generation

D) Evolution
E) Endosymbiotic theory

CORRECT ANSWER: C RATIONALE: Pasteur's swan-neck flask experiments
showed that broth remained sterile when not exposed to airborne particles, decisively
disproving spontaneous generation — the idea that life could arise from non-living
matter.

,Question 5 Robert Koch's postulates are used to:

A) Classify viruses

B) Establish that a specific microorganism causes a specific disease

C) Measure microbial growth rates

D) Determine antibiotic resistance

E) Describe cellular respiration

CORRECT ANSWER: B RATIONALE: Koch's postulates are a series of four criteria
designed to establish a causal relationship between a microorganism and a disease,
forming the foundation of modern infectious disease research.


Question 6 Which of the following is NOT one of Koch's postulates?

A) The microorganism must be found in all cases of the disease

B) The microorganism must be isolated from the diseased host

C) The isolated microorganism must cause disease when introduced to a healthy
host

D) The microorganism must be re-isolated from the experimentally diseased host

E) The microorganism must be visible to the naked eye

CORRECT ANSWER: E RATIONALE: Koch's postulates do not require the pathogen
to be visible to the naked eye. The four criteria involve finding the organism in disease,
isolating it, reproducing disease, and re-isolating the same organism — size is
irrelevant.



Question 7 What is the term for microorganisms that cause disease?

A) Saprophytes

B) Commensals

C) Pathogens

D) Mutualists
E) Autotrophs

, CORRECT ANSWER: C RATIONALE: Pathogens are microorganisms capable of
causing disease in a host. The term comes from the Greek "pathos" (suffering) and
"genes" (producer).


Question 8 Which branch of microbiology focuses on fungi?

A) Virology

B) Bacteriology

C) Parasitology

D) Mycology

E) Immunology

CORRECT ANSWER: D RATIONALE: Mycology is the branch of microbiology
dedicated to the study of fungi, including yeasts, molds, and mushrooms. It includes the
study of their genetics, biochemical properties, and medical significance.



Question 9 The discipline that studies viruses is called:
A) Bacteriology

B) Mycology

C) Virology

D) Parasitology
E) Epidemiology

CORRECT ANSWER: C RATIONALE: Virology is the scientific study of viruses —
their structure, classification, and evolution, as well as the diseases they cause and their
use in research and therapy.



Question 10 Normal flora refers to:

A) Plants that grow in sterile environments

B) Microorganisms that permanently or transiently inhabit the body without
causing disease

C) Pathogenic bacteria only