Question 1

Which of the following best describes the difference between a pathogen and an opportunistic pathogen?

Accepted Answer

A pathogen always causes disease in humans, while an opportunistic pathogen causes disease only in a weakened host.

Question 2

Which experiment by Louis Pasteur provided strong evidence against spontaneous generation?

Accepted Answer

He boiled broth in S-necked flasks, showing that life did not arise unless exposed to airborne microbes.

Question 3

Which of the following is NOT a step in Koch’s postulates?

Accepted Answer

The organism must be shown to mutate in the host.

Question 4

Which scientist is credited with introducing handwashing to reduce mortality from childbed fever in hospitals?

Accepted Answer

Ignaz Semmelweis

Question 5

Which of the following is a correct statement about the scientific method?

Accepted Answer

A hypothesis is proposed, then observations are collected and analyzed to draw a conclusion.

Question 6

Which of the following is an example of a nonliving microbe studied in microbiology?

Accepted Answer

Viruses

Question 7

Which of the following best describes the difference between a scientific law and a scientific theory?

Accepted Answer

A law predicts what happens, while a theory explains how and why something occurs.

Question 8

Which of the following is NOT a function of the normal microbiota?

Accepted Answer

Causing disease in all hosts

Question 9

A woman takes antibiotics for a urinary tract infection and subsequently develops a vaginal yeast infection. This is best explained by:

Accepted Answer

The antibiotics killed the normal vaginal microbiota, allowing opportunistic pathogens like Candida albicans to grow.

Question 10

Which of the following is the correct order of the taxonomic hierarchy from broadest to most specific?

Accepted Answer

Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species

Question 11

Which of the following statements about prokaryotic and eukaryotic cells is correct?

Accepted Answer

Prokaryotic cells include bacteria and archaea, while eukaryotic cells include fungi, protists, and animals.

Question 12

Which of the following is a real-world example of an aseptic technique used to prevent healthcare-acquired infections (HAIs)?

Accepted Answer

Wearing gloves during patient care

Question 13

Which of the following best describes the concept of biogenesis?

Accepted Answer

Life emerges from existing life.

Question 14

Which of the following is true about the Human Microbiome Project (HMP)?

Accepted Answer

It aims to characterize all of the microbes in and on our bodies.

Question 15

Which of the following is a plausible reason why we may never have a complete catalog of every infectious agent?

Accepted Answer

New diseases emerge and only about 2% of bacteria can be cultured in the laboratory.

Question 16

Which of the following is an example of transient microbiota?

Accepted Answer

Microbes picked up from a handshake that are removed by handwashing

Question 17

Which of the following is NOT a correct statement about binomial nomenclature?

Accepted Answer

The species name is capitalized.

Question 18

Which of the following best explains why normal microbiota can sometimes include pathogens?

Accepted Answer

The location of the microbe in the body can determine whether it acts as a harmless resident or a pathogen.

Question 19

Which of the following is a correct application of Koch’s postulates in a clinical scenario?

Accepted Answer

A bacterium is isolated from a sick patient, grown in pure culture, and causes the same disease when introduced into a healthy animal.

Introduction to Microbiology: Basic Principles and Historical Foundations

Study Guide - Practice Questions