Question 1

Which of the following best describes the main focus of microbiology?

Accepted Answer

The study of microorganisms or microbes, which are often invisible to the naked eye

Question 2

Which scientist is credited with disproving the theory of spontaneous generation and supporting biogenesis through his swan-neck flask experiment?

Accepted Answer

Louis Pasteur

Question 3

A hospital is experiencing a high rate of healthcare-associated infections (HAIs). Which of the following practices would be LEAST effective in reducing HAIs?

Accepted Answer

Using the same gloves for multiple patients

Question 4

Which of the following statements about Koch’s postulates is correct?

Accepted Answer

They provide a systematic method to link a specific microbe to a specific disease.

Question 5

Which of the following is an example of a mutualistic relationship between humans and their microbiota?

Accepted Answer

Gut bacteria that help digest food and produce vitamins

Question 6

Which of the following best distinguishes a scientific theory from a scientific law?

Accepted Answer

A law is a precise statement or mathematical formula that predicts a specific occurrence, while a theory explains how and why something occurs.

Question 7

A patient is diagnosed with a disease caused by an opportunistic pathogen. Which scenario most likely led to this infection?

Accepted Answer

The patient had a weakened immune system after chemotherapy.

Question 8

Which of the following best describes the function of a mordant in a staining procedure?

Accepted Answer

It interacts with a dye to fix it on or inside a treated specimen.

Question 9

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

Accepted Answer

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

Question 10

Which of the following best explains why basic dyes are commonly used to stain bacterial cells?

Accepted Answer

Bacterial cell surfaces are negatively charged and attract the positively charged basic dyes.

Question 11

A microbiologist wants to visualize live, unstained cells to observe their movement. Which microscopy technique should they use?

Accepted Answer

Phase contrast microscopy

Question 12

Which of the following statements about biofilms is correct?

Accepted Answer

Biofilms are sticky communities that can include single or diverse microbial species.

Question 13

Which of the following best describes the difference between normal microbiota and transient microbiota?

Accepted Answer

Normal microbiota are stable residents of the body, while transient microbiota are temporary and can be removed by hygiene.

Question 14

Which of the following staining techniques would be most appropriate to visualize bacterial endospores?

Accepted Answer

Endospore stain using malachite green and safranin

Question 15

A scientist is using a fluorescent dye that absorbs ultraviolet (UV) light and emits visible light. What is this process called?

Accepted Answer

Fluorescence

Question 16

Which of the following best explains why electron microscopes have higher resolution than light microscopes?

Accepted Answer

Electron microscopes use smaller wavelengths than visible light.

Question 17

A sample is stained with a dye that is repelled by the negatively charged bacterial cell surface, resulting in a dark background and clear cells. Which type of stain is being used?

Accepted Answer

Acidic (negative) stain

Question 18

Which of the following is a correct application of the scientific method in microbiology?

Accepted Answer

Formulating a hypothesis, conducting experiments, and analyzing results to draw conclusions

Question 19

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

Accepted Answer

Causing disease in all individuals

Question 20

A microbiologist is trying to isolate a single species of bacteria from a mixed culture. Which technique should they use to obtain isolated colonies?

Accepted Answer

Streak plate technique

Chapter 1: Introduction to Microbiology – Study Notes

Study Guide - Practice Questions

Study Guide - Flashcards