Question 1

Which of the following statements best describes the main contribution of Louis Pasteur to microbiology?

Accepted Answer

He demonstrated that life does not arise spontaneously from nonliving matter.

Question 2

Which of the following is NOT a function of microbes in the environment or industry?

Accepted Answer

Causing all infectious diseases

Question 3

Which of the following best explains why Gram-positive bacteria appear purple after Gram staining?

Accepted Answer

They have a thick peptidoglycan layer that retains the crystal violet-iodine complex.

Question 4

Which of the following is a correct sequence of reagents used in the Gram stain procedure?

Accepted Answer

Crystal violet, iodine, ethanol, safranin

Question 5

Which scientist is credited with the development of aseptic techniques and the process of pasteurization?

Accepted Answer

Louis Pasteur

Question 6

Which of the following is a distinguishing feature of Archaea compared to Bacteria?

Accepted Answer

Archaea lack peptidoglycan in their cell walls.

Question 7

A patient presents with a persistent cough and a positive acid-fast stain. Which genus is most likely responsible for the infection?

Accepted Answer

Mycobacterium

Question 8

Which of the following best describes the endosymbiotic theory?

Accepted Answer

Eukaryotic cells evolved from prokaryotic cells living inside one another.

Question 9

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

Accepted Answer

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

Question 10

Which of the following microscopes would be most appropriate for viewing live, unstained spirochetes such as Treponema pallidum?

Accepted Answer

Darkfield microscope

Question 11

A laboratory technician is preparing a bacterial smear for Gram staining. Why is heat fixation necessary before staining?

Accepted Answer

To adhere the bacteria to the slide and kill them

Question 12

Which of the following is a reason why viruses are not classified in any of the five kingdoms?

Accepted Answer

They are acellular and lack cellular structure.

Question 13

Which of the following best explains why an aerosolized agent is considered the most likely method for a biological attack?

Accepted Answer

It can be easily disseminated and inhaled by large populations.

Question 14

Which of the following stains is used to identify bacteria with a waxy cell wall, such as Mycobacterium tuberculosis?

Accepted Answer

Acid-fast stain

Question 15

Which of the following is a correct statement about prokaryotic DNA?

Accepted Answer

It is double-stranded and circular.

Question 16

Which of the following is a function of the bacterial capsule (glycocalyx)?

Accepted Answer

It allows the organism to resist host defenses such as phagocytosis.

Question 17

Which of the following is the best description of the role of Koch’s postulates in microbiology?

Accepted Answer

They are experimental steps that relate a specific microbe to a specific disease.

Question 18

Which of the following is a correct conversion based on the units of measure used in microscopy?

Accepted Answer

$$1\ \mathrm{mm} = 1000\ \mathrm{\mu m}$$

Question 19

Which of the following is a real-world example of bioterrorism involving a bacterial agent?

Accepted Answer

The 2001 U.S. Anthrax Attack

BIO 201 Unit 1: Introduction to Microbiology – Foundations, Classification, Microscopy, and Bioterrorism

Study Guide - Practice Questions